Dealer twice in 1 day, going back again

[ppfd]

Does nothing, zero zip when you use the key
It will remote/start with the key fob.
Dies as soon as you put it in gear

Sponsored

 

[airline tech]

Ok, I think he is getting both sides of the starting issue, Crank and No Crank

And since he is able to (sometimes) remote start and then when he turns the (Keyed) ignition and places in gear (Dies)

With that said, I am going back to one of my initial thoughts and that is the Ignition Switch itself.
and the reason is. Inside the Ignition Switch is a (Key in Ignition) Sensor which is tied to the Anti-Theft System.
This is the reason I recommended him to jiggle key and see if he could generate it to fault.
From the Ignition switch, next possible is the PCM Power Relay and then Run Start Relay

Edit:
Note: And this will possibly explain why, you are able to remote start the truck and then it dies when key is turned to run (and put in gear)
Remote Start is bypassing the Ign Switch, and you only have a partially powered truck, once you place key in the ignition switch and turn it to run, you are powering the entire system.
Now this requires a Valid Key-In Ignition signal for this to happen and normally the Anti-Theft system will not shut down a running engine, but since you are remote starting, and have engine the running, I think it is shutting down, due to a invalid key in ignition signal when you placed it in gear

Please note the Partially Powered part of this, as the Key-In Ignition signal will tie into ALL of the issues you have.

1. No Start - With Key
2. Truck Dies - With Key (After Remote Start)
3. All Modules not seeing that truck (Ign Switch) is in Run and Engine is Running, thus the only thing it is possibly seeing is a remote start (Power) situation and generates the communication faults.

If I am correct, did you lose the radio when it faulted? If so, I think I am on the right path.

So, again another finger point in the right possible direction.

If I recall, there is a PID Data Reference you can monitor with scanner, as key is put in (Valid) and pulled out (Invalid) or it will be a voltage reading with key in (The voltage reading comes from the tumbler set) within the Switch (The BCM has to see this as a valid key) to allow start.
(Anti-Theft) Protection
I think Ford - Uses (PiD) Data - PATS , Enable or Disable (Anti-Theft) System

So, for the Power Feed side of the Starting Issue which ties into the other faults, I still think the Ignition Switch and or Run/Start Relay is the issue.
Then if this check is good, then check the Ground G-108
If the Ground is Good, then move on to the (Communication) troubleshooting.

I will say again, you need to focus on anything that gets switched, actuated, pressed when you have intermittent faults like this, being that it is not hard faulted, I am using his descriptions and looking at Wiring Diagrams and saying (What If)
Now a bad wire connection can tie into this, but with it being so intermittent, I keep thinking the Ignition Switch is the issue and now the What If? (What if the Key-In Ignition Signal is Valid Enough to allow truck to start) but put the truck in a Limp Mode situation or something is only getting partially powered due to not obtaining a truly valid signal that the key is in the switch.
(Possible Voltage-Data) Key In, just outside of specs

Now the OP Stated that he lost power steering, but never stated to what extent.
The PSCM - Has 2 Failure Modes: Reduced Power Steering Assist and Manual Steering, a Low battery voltage and or invalid signal can cause these failure modes, so this is why, this also needs to be included as a possible, I am using his description of something he physically lost.
and the Code C0051 Pinpoint Test will address this issue, as this is the most likely Fault in the List to start with.
You could look at all of them and dig into them, but that will take a few days to complete.
which leads me to think Outside the Box.

If you only focus on the fault tree (Long List) you will not see anything related to Voltage Loss
so, this particular issue, requires you to be attentive to all troubles the truck is presenting.

Now the COM bus may be preventing the no-start issue as all the modules are not being powered and or sending the information along the Bus, can very well still be the issue.
and with those faults, just visually you are possibly leading down the wrong path.

The main reason, I am thinking outside the box, is there are no codes related to the starting issues and if the modules are not seeing that the truck is running, then it's generating the Communication faults, so I placed my focal point there.

I actually like these types of issues; it helps me learn the system and forces me to think outside the box as the Ford Service Manuals are sometimes vague and or misleading.

I am very interested in what the fault actually is. I am intrigued and invested in a solution. Hopefully the Dealer will find the solution, all I can do is offer some possible points to check from this Office Chair.
The Ford Tech has to be dedicated to finding a solution and possibly spend a few days with just this truck and not worry about the boss (hanging over your shoulder) how much longer you going to be, we have other vehicles to get into the shop.

To, the OP, please tell them your issues starting the truck, as you stated here, that issue alone may just be the shortcut they need. Do a complete test on that Ign Switch and see if any of the PID data is intermittently out of spec ranges.

 

[Max Crafter]

it makes a big difference if it cranks or not.

 

[Jason B]

Ok, I think he is getting both sides of the starting issue, Crank and No Crank

And since he is able to (sometimes) remote start and then when he turns the (Keyed) ignition and places in gear (Dies)

With that said, I am going back to one of my initial thoughts and that is the Ignition Switch itself.
and the reason is. Inside the Ignition Switch is a (Key in Ignition) Sensor which is tied to the Anti-Theft System.
This is the reason I recommended him to jiggle key and see if he could generate it to fault.
From the Ignition switch, next possible is the PCM Power Relay and then Run Start Relay

Edit:
Note: And this will possibly explain why, you are able to remote start the truck and then it dies when key is turned to run (and put in gear)
Remote Start is bypassing the Ign Switch, and you only have a partially powered truck, once you place key in the ignition switch and turn it to run, you are powering the entire system.
Now this requires a Valid Key-In Ignition signal for this to happen and normally the Anti-Theft system will not shut down a running engine, but since you are remote starting, and have engine the running, I think it is shutting down, due to a invalid key in ignition signal when you placed it in gear

Please note the Partially Powered part of this, as the Key-In Ignition signal will tie into ALL of the issues you have.

1. No Start - With Key
2. Truck Dies - With Key (After Remote Start)
3. All Modules not seeing that truck (Ign Switch) is in Run and Engine is Running, thus the only thing it is possibly seeing is a remote start (Power) situation and generates the communication faults.

If I am correct, did you lose the radio when it faulted? If so, I think I am on the right path.

So, again another finger point in the right possible direction.

If I recall, there is a PID Data Reference you can monitor with scanner, as key is put in (Valid) and pulled out (Invalid) or it will be a voltage reading with key in (The voltage reading comes from the tumbler set) within the Switch (The BCM has to see this as a valid key) to allow start.
(Anti-Theft) Protection
I think Ford - Uses (PiD) Data - PATS , Enable or Disable (Anti-Theft) System

So, for the Power Feed side of the Starting Issue which ties into the other faults, I still think the Ignition Switch and or Run/Start Relay is the issue.
Then if this check is good, then check the Ground G-108
If the Ground is Good, then move on to the (Communication) troubleshooting.

I will say again, you need to focus on anything that gets switched, actuated, pressed when you have intermittent faults like this, being that it is not hard faulted, I am using his descriptions and looking at Wiring Diagrams and saying (What If)
Now a bad wire connection can tie into this, but with it being so intermittent, I keep thinking the Ignition Switch is the issue and now the What If? (What if the Key-In Ignition Signal is Valid Enough to allow truck to start) but put the truck in a Limp Mode situation or something is only getting partially powered due to not obtaining a truly valid signal that the key is in the switch.
(Possible Voltage-Data) Key In, just outside of specs

Now the OP Stated that he lost power steering, but never stated to what extent.
The PSCM - Has 2 Failure Modes: Reduced Power Steering Assist and Manual Steering, a Low battery voltage and or invalid signal can cause these failure modes, so this is why, this also needs to be included as a possible, I am using his description of something he physically lost.
and the Code C0051 Pinpoint Test will address this issue, as this is the most likely Fault in the List to start with.
You could look at all of them and dig into them, but that will take a few days to complete.
which leads me to think Outside the Box.

If you only focus on the fault tree (Long List) you will not see anything related to Voltage Loss
so, this particular issue, requires you to be attentive to all troubles the truck is presenting.

Now the COM bus may be preventing the no-start issue as all the modules are not being powered and or sending the information along the Bus, can very well still be the issue.
and with those faults, just visually you are possibly leading down the wrong path.

The main reason, I am thinking outside the box, is there are no codes related to the starting issues and if the modules are not seeing that the truck is running, then it's generating the Communication faults, so I placed my focal point there.

I actually like these types of issues; it helps me learn the system and forces me to think outside the box as the Ford Service Manuals are sometimes vague and or misleading.

I am very interested in what the fault actually is. I am intrigued and invested in a solution. Hopefully the Dealer will find the solution, all I can do is offer some possible points to check from this Office Chair.
The Ford Tech has to be dedicated to finding a solution and possibly spend a few days with just this truck and not worry about the boss (hanging over your shoulder) how much longer you going to be, we have other vehicles to get into the shop.

To, the OP, please tell them your issues starting the truck, as you stated here, that issue alone may just be the shortcut they need. Do a complete test on that Ign Switch and see if any of the PID data is intermittently out of spec ranges.

A bad wiring connection, like the wiring he did for his AUX lighting?
I remember someone telling me that if you have a problem after installing something, the first thing to do is uninstall it and go back to previous setup. See if the problem goes away.

Edit: I really appreciate all the technical help you provide here on this forum.

 

[ppfd]

Airline you need to work for my ford garage.

When using the key there is nothing, not a sound, just like as if the truck has no battery or even an engine it it.
When using the key fob it fires right up.
Key in the ignition it tuns to run, and runs until you move the trans lever into gear then dies.
And as a running theme here, it does all this sometimes. Though now it is the main issue along with the codes.
The main tech as they call him won’t be back till next week.
And the service manager says ford won’t give me a loaner until he evaluates the truck.
Going to call and email the gal that opened the case and see what she says.

.

 

[Jason B]

Airline you need to work for my ford garage.

When using the key there is nothing, not a sound, just like as if the truck has no battery or even an engine it it.
When using the key fob it fires right up.
Key in the ignition it tuns to run, and runs until you move the trans lever into gear then dies.
And as a running theme here, it does all this sometimes. Though now it is the main issue along with the codes.
The main tech as they call him won’t be back till next week.
And the service manager says ford won’t give me a loaner until he evaluates the truck.
Going to call and email the gal that opened the case and see what she says.

.

Once it dies when put in gear, can you restart the truck with the fob (park or neutral) with the key in the ignition, or out of the ignition, but in close proximity to the switch? As airline tech said, it could be PATS related.

 

[21Blackout]

sorry that I'm so late to this party but if you can do me a favor and get me your vin @ppfd ill spitball this with my senior master tech of 11yrs been with ford for 14yrs right now as it stands, I'm thinking PSCM but want to look at connected data first.

 

[seasprite]

Ok, I think he is getting both sides of the starting issue, Crank and No Crank

And since he is able to (sometimes) remote start and then when he turns the (Keyed) ignition and places in gear (Dies)

With that said, I am going back to one of my initial thoughts and that is the Ignition Switch itself.
and the reason is. Inside the Ignition Switch is a (Key in Ignition) Sensor which is tied to the Anti-Theft System.
This is the reason I recommended him to jiggle key and see if he could generate it to fault.
From the Ignition switch, next possible is the PCM Power Relay and then Run Start Relay

Edit:
Note: And this will possibly explain why, you are able to remote start the truck and then it dies when key is turned to run (and put in gear)
Remote Start is bypassing the Ign Switch, and you only have a partially powered truck, once you place key in the ignition switch and turn it to run, you are powering the entire system.
Now this requires a Valid Key-In Ignition signal for this to happen and normally the Anti-Theft system will not shut down a running engine, but since you are remote starting, and have engine the running, I think it is shutting down, due to a invalid key in ignition signal when you placed it in gear

Please note the Partially Powered part of this, as the Key-In Ignition signal will tie into ALL of the issues you have.

1. No Start - With Key
2. Truck Dies - With Key (After Remote Start)
3. All Modules not seeing that truck (Ign Switch) is in Run and Engine is Running, thus the only thing it is possibly seeing is a remote start (Power) situation and generates the communication faults.

If I am correct, did you lose the radio when it faulted? If so, I think I am on the right path.

So, again another finger point in the right possible direction.

If I recall, there is a PID Data Reference you can monitor with scanner, as key is put in (Valid) and pulled out (Invalid) or it will be a voltage reading with key in (The voltage reading comes from the tumbler set) within the Switch (The BCM has to see this as a valid key) to allow start.
(Anti-Theft) Protection
I think Ford - Uses (PiD) Data - PATS , Enable or Disable (Anti-Theft) System

So, for the Power Feed side of the Starting Issue which ties into the other faults, I still think the Ignition Switch and or Run/Start Relay is the issue.
Then if this check is good, then check the Ground G-108
If the Ground is Good, then move on to the (Communication) troubleshooting.

I will say again, you need to focus on anything that gets switched, actuated, pressed when you have intermittent faults like this, being that it is not hard faulted, I am using his descriptions and looking at Wiring Diagrams and saying (What If)
Now a bad wire connection can tie into this, but with it being so intermittent, I keep thinking the Ignition Switch is the issue and now the What If? (What if the Key-In Ignition Signal is Valid Enough to allow truck to start) but put the truck in a Limp Mode situation or something is only getting partially powered due to not obtaining a truly valid signal that the key is in the switch.
(Possible Voltage-Data) Key In, just outside of specs

Now the OP Stated that he lost power steering, but never stated to what extent.
The PSCM - Has 2 Failure Modes: Reduced Power Steering Assist and Manual Steering, a Low battery voltage and or invalid signal can cause these failure modes, so this is why, this also needs to be included as a possible, I am using his description of something he physically lost.
and the Code C0051 Pinpoint Test will address this issue, as this is the most likely Fault in the List to start with.
You could look at all of them and dig into them, but that will take a few days to complete.
which leads me to think Outside the Box.

If you only focus on the fault tree (Long List) you will not see anything related to Voltage Loss
so, this particular issue, requires you to be attentive to all troubles the truck is presenting.

Now the COM bus may be preventing the no-start issue as all the modules are not being powered and or sending the information along the Bus, can very well still be the issue.
and with those faults, just visually you are possibly leading down the wrong path.

The main reason, I am thinking outside the box, is there are no codes related to the starting issues and if the modules are not seeing that the truck is running, then it's generating the Communication faults, so I placed my focal point there.

I actually like these types of issues; it helps me learn the system and forces me to think outside the box as the Ford Service Manuals are sometimes vague and or misleading.

I am very interested in what the fault actually is. I am intrigued and invested in a solution. Hopefully the Dealer will find the solution, all I can do is offer some possible points to check from this Office Chair.
The Ford Tech has to be dedicated to finding a solution and possibly spend a few days with just this truck and not worry about the boss (hanging over your shoulder) how much longer you going to be, we have other vehicles to get into the shop.

To, the OP, please tell them your issues starting the truck, as you stated here, that issue alone may just be the shortcut they need. Do a complete test on that Ign Switch and see if any of the PID data is intermittently out of spec ranges.

Like you I'm curious what the cause is and want to see it fixed.

 

[ppfd]

sorry that I'm so late to this party but if you can do me a favor and get me your vin @ppfd ill spitball this with my senior master tech of 11yrs been with ford for 14yrs right now as it stands, I'm thinking PSCM but want to look at connected data first.

Thanks and I will
Reference the key. I locked the doors while sitting in the truck and then started the truck with the fob, put the key in the ignition, turned it to run and then put the truck in drive and it died. Tried the above 2 or 3 times.

 

[airline tech]

Just curious, do you get any wake up of any kind when you open the driver's door without Remote Start? (Important Knowledge)

Mainly Fuel Pump - Prime
Dash Power Up
Dome Lights

and when you turn the key to run, are the dash lights coming on and no-start.
or No power at all anywhere?

This may help pinpoint it down some
I want to rule out the Door Ajar Switch as a possible

 

[airline tech]

I did figure out, one issue - The reason it dies when you go to drive:
It's in the list: P1595, this is a normal safety feature.
If Remote Start is active and truck was to come out of gear (Park), it forces engine shutdown.
(You are moving gear selector to drive)
When you put key in the ignition and go to run - the truck still thinks you are in a remote start situation when you move gear to drive and kills the engine
So, this is another pointer to that Ignition Switch and Related relays as a highly suspect issue, or communication bus is dead to relay the information

 

[airline tech]

I FOUND IT, here is the Problem.

This is going to be a detailed post, so all can see and understand how I came to my solution.

In my wanting to learn what is actually powered in (Remote Start) I dug into the Power Distibution diagram and found the problem.

I am certain to 100% I have found the problem and its down to (1) little item.

I am attaching a PDF of this as well for clarity, I wanted to show color highlights, but it gets blurry when I insert image.

If you follow along the top of the page: (From Left)
Power From PCM Relay and note all modules being powered up to the Run/Start Relay
You are looking at the Remote Start Side of Power, note it will allow engine to run as you will have power coming off of the PCM Power Relay to the FCIM and the required Relays, Fuel Pump and Injectors for engine to start and run (Bare Minimum), this includes the Power Point Relays, so your power ports and whatever you have plugged in will have power.
So, this rules out, the item you had plugged in as the issue, unless you have lighting issues in addition to the no-start/driving, and it comes into play if it only does it (faults) when plugged into the power port, might be robbing power from the Run/Start Relay (I dont think this is causing any issues though) just a possible in this whole issue.

You also have power to the exterior lights off of that PCM Relay, so this also rules out the Lighted Grille as a cause until you apply a ground to the other side of the Run/Start Relay
Note: Where the Exterior Lighting is on that Power Feed, it's after the Run/Start Relay
Now it is possible, that the (Grille Lights) are pulling too much power and robbing power for the Run/Start Relay to have full voltage needed for it to operate.
It will not show up, until you add the Run/Start relay into the mix, by adding a power feed.
So, with this diagram I have proven that YES, a simple LED light being added to the Ranger may cause issues.

In Remote Start, you have power up to the (Run/Start) Relay but not past it. The Run/Start Relay circuit is completed via the Ignition Switch and BCM (Ground Signal)

Note the (2) Power Legs on the Run/Start Relay, (1) is for the BCM and (1) is for the rest of the modules, when the BCM provides the Ground, it allows the BCM circuit to complete, this also closes the power leg (Output) to the rest of the modules. (Within the relay)

Note: There is no Fuse between the PCM Power relay and the Run/Start Relay, it is direct power feed.

The Run/Start relay does not come in to play with Remote Start, it only comes into the circuit with the Ignition Switch - this is part of the PATS system (Anti-Theft) requires a Valid Key signal from the BCM and PCM and Key and PATS System

If you look past the Run/Start relay you will see all the modules that are getting power from that relay, note that the PCM, PSCM and ABS are receiving a power signal from that Run/Start Relay and telling the truck, (Key is in-Ignition) and switch is in (Run/Start) Position


So, the issue is the Run/Start Relay not being powered properly. (Possible Reasons Why)

1. Run/Start Relay itself is bad - (Needs Voltage and Ground Checks at the Relay) to ensure no abnormal readings or issue may return if you just replace it.

2. Bad Wire - Connection -(Power) Between the (2) relays PCM and Run/Start, I doubt this but cannot rule it out, as you are able to remote start, this should be good.

3. Bad Ignition Switch, not providing a valid signal to the BCM to allow a ground signal to the other side of the (Run/Start) relay. (To Complete the Circuit)

4. Bad wiring between the Ignition Switch and BCM

5. Bad BCM, not providing the Ground Signal to the Run/Start Relay

6. Bad Wire between the BCM and Run/Start Relay (Ground Signal)

7. Problem with the PATS system, not allowing the BCM to provide the Ground Signal to the Run/Start relay.

8. Grille Lights or Exterior Lighting, drawing too much power, creating a voltage loss at the Run/Start Relay

But when you take all of the Faults and Compare them to the Possible Problem, (Run/Start) Relay
You will find (Zero) specific codes directing you to it.

Now that I gave you all the possible issues, let's think outside the box here and play What-If
But first let's try to rule out some of the possibles.
1. You have (0) Codes related to PATS
2. You have (0) Codes related to BCM, except Communication
3. You have (3) Codes related to PCM, except Communication
4. You have (0) Codes related to Ignition Switch
5. You have (1) Code related to the ABS System except Communication

What you do have:

The PCM receives power a input from that Run/Start Relay, but since it is not Powered (Fully)
you see these Fault Codes on your List.
Brake Booster, Brake Switch Signal and Force Engine Shutdown

The ABS and PSCM receives power from the Run/Start Relay, but since they are not being powered fully you see the fault code Steering Wheel Position Sensor from the PSCM Module generating it and ABS Module Reporting it

and a long list of Communication Codes

HMM, now we have something to look at and play what-if?

Remember, I said to look at something that is switched, pressed actuated on a frequent basis for intermittent faults like this?
The Run/Start Relay - Is included in this little trick.

Right Now, the Run Start/Relay is Hard Faulted, and is not working, thus no start and most likely bad, not allowing both (2) circuits to complete.

Now for the What-If, this would explain the reason you have it running and driving it with all of the fault codes.
Let's say, the BCM provided the ground, and the Run/Start relay was only doing 1/2 of its job function.
It has 2
1. Provide the Ground, BCM to allow for the Ignition Key Start and remain powered when in Run.
2. The completed circuit above - will allow the Power Feed (Output) to the modules.

So, What IF?
The relay was only providing the Ground for the BCM to allow the truck to start with the key, but not closing the relay to allow power (output) to the modules. (Stuck Closed)
This will defiantly give you your fault tree of death.

So, you now have a Run/Start Relay not accepting power/ground (Dead) No Start with Key Condition and a (Sticking) Relay when you were able to drive it.

Now, the relay is just bad, or it has a voltage loss, (Not enough Voltage to Close) the Relay, from just a coincidence and a poor connection or Power Point (Plugged) in at the time of every fault or the Grille Lights.

I am ruling out all the modules that are powered by the Run/Start Relay, as they are individually fuse protected and I do not see anything that would take out the whole circuit.

So, check the Grille Lights and Wiring and Check Voltage Reading at Relay if good just replace the relay, you have a 50 AMP fuse protecting those exterior lights, for shorts and have internal protection from the BCM (FET) to protect the circuit (internal of BCM)
BUT, thinking outside the box, think What If? they were pulling too much voltage from the circuit run. (Possible) it can be robbing needed power.
Hopefully, the Ford Tech will listen to you, and tell him what to look at, I am highly certain this is the problem. The Run/Start Relay and or Voltage / Ground issue at the Relay itself.
As this little relay, ties into ALL faults and Start/Driving Issues - The Common Between all of them that I was looking for.

 

[seasprite]

I FOUND IT, here is the Problem.

This is going to be a detailed post, so all can see and understand how I came to my solution.

In my wanting to learn what is actually powered in (Remote Start) I dug into the Power Distibution diagram and found the problem.

I am certain to 100% I have found the problem and its down to (1) little item.

I am attaching a PDF of this as well for clarity, I wanted to show color highlights, but it gets blurry when I insert image.

If you follow along the top of the page: (From Left)
Power From PCM Relay and note all modules being powered up to the Run/Start Relay
You are looking at the Remote Start Side of Power, note it will allow engine to run as you will have power coming off of the PCM Power Relay to the FCIM and the required Relays, Fuel Pump and Injectors for engine to start and run (Bare Minimum), this includes the Power Point Relays, so your power ports and whatever you have plugged in will have power.
So, this rules out, the item you had plugged in as the issue, unless you have lighting issues in addition to the no-start/driving, and it comes into play if it only does it (faults) when plugged into the power port, might be robbing power from the Run/Start Relay (I dont think this is causing any issues though) just a possible in this whole issue.

You also have power to the exterior lights off of that PCM Relay, so this also rules out the Lighted Grille as a cause until you apply a ground to the other side of the Run/Start Relay
Note: Where the Exterior Lighting is on that Power Feed, it's after the Run/Start Relay
Now it is possible, that the (Grille Lights) are pulling too much power and robbing power for the Run/Start Relay to have full voltage needed for it to operate.
It will not show up, until you add the Run/Start relay into the mix, by adding a power feed.
So, with this diagram I have proven that YES, a simple LED light being added to the Ranger may cause issues.

In Remote Start, you have power up to the (Run/Start) Relay but not past it. The Run/Start Relay circuit is completed via the Ignition Switch and BCM (Ground Signal)

Note the (2) Power Legs on the Run/Start Relay, (1) is for the BCM and (1) is for the rest of the modules, when the BCM provides the Ground, it allows the BCM circuit to complete, this also closes the power leg (Output) to the rest of the modules. (Within the relay)

Note: There is no Fuse between the PCM Power relay and the Run/Start Relay, it is direct power feed.

The Run/Start relay does not come in to play with Remote Start, it only comes into the circuit with the Ignition Switch - this is part of the PATS system (Anti-Theft) requires a Valid Key signal from the BCM and PCM and Key and PATS System

If you look past the Run/Start relay you will see all the modules that are getting power from that relay, note that the PCM, PSCM and ABS are receiving a power signal from that Run/Start Relay and telling the truck, (Key is in-Ignition) and switch is in (Run/Start) Position


So, the issue is the Run/Start Relay not being powered properly. (Possible Reasons Why)

1. Run/Start Relay itself is bad - (Needs Voltage and Ground Checks at the Relay) to ensure no abnormal readings or issue may return if you just replace it.

2. Bad Wire - Connection -(Power) Between the (2) relays PCM and Run/Start, I doubt this but cannot rule it out, as you are able to remote start, this should be good.

3. Bad Ignition Switch, not providing a valid signal to the BCM to allow a ground signal to the other side of the (Run/Start) relay. (To Complete the Circuit)

4. Bad wiring between the Ignition Switch and BCM

5. Bad BCM, not providing the Ground Signal to the Run/Start Relay

6. Bad Wire between the BCM and Run/Start Relay (Ground Signal)

7. Problem with the PATS system, not allowing the BCM to provide the Ground Signal to the Run/Start relay.

8. Grille Lights or Exterior Lighting, drawing too much power, creating a voltage loss at the Run/Start Relay

But when you take all of the Faults and Compare them to the Possible Problem, (Run/Start) Relay
You will find (Zero) specific codes directing you to it.

Now that I gave you all the possible issues, let's think outside the box here and play What-If
But first let's try to rule out some of the possibles.
1. You have (0) Codes related to PATS
2. You have (0) Codes related to BCM, except Communication
3. You have (3) Codes related to PCM, except Communication
4. You have (0) Codes related to Ignition Switch
5. You have (1) Code related to the ABS System except Communication

What you do have:

The PCM receives power a input from that Run/Start Relay, but since it is not Powered (Fully)
you see these Fault Codes on your List.
Brake Booster, Brake Switch Signal and Force Engine Shutdown

The ABS and PSCM receives power from the Run/Start Relay, but since they are not being powered fully you see the fault code Steering Wheel Position Sensor from the PSCM Module generating it and ABS Module Reporting it

and a long list of Communication Codes

HMM, now we have something to look at and play what-if?

Remember, I said to look at something that is switched, pressed actuated on a frequent basis for intermittent faults like this?
The Run/Start Relay - Is included in this little trick.

Right Now, the Run Start/Relay is Hard Faulted, and is not working, thus no start and most likely bad, not allowing both (2) circuits to complete.

Now for the What-If, this would explain the reason you have it running and driving it with all of the fault codes.
Let's say, the BCM provided the ground, and the Run/Start relay was only doing 1/2 of its job function.
It has 2
1. Provide the Ground, BCM to allow for the Ignition Key Start and remain powered when in Run.
2. The completed circuit above - will allow the Power Feed (Output) to the modules.

So, What IF?
The relay was only providing the Ground for the BCM to allow the truck to start with the key, but not closing the relay to allow power (output) to the modules. (Stuck Closed)
This will defiantly give you your fault tree of death.

So, you now have a Run/Start Relay not accepting power/ground (Dead) No Start with Key Condition and a (Sticking) Relay when you were able to drive it.

Now, the relay is just bad, or it has a voltage loss, (Not enough Voltage to Close) the Relay, from just a coincidence and a poor connection or Power Point (Plugged) in at the time of every fault or the Grille Lights.

I am ruling out all the modules that are powered by the Run/Start Relay, as they are individually fuse protected and I do not see anything that would take out the whole circuit.

So, check the Grille Lights and Wiring and Check Voltage Reading at Relay if good just replace the relay, you have a 50 AMP fuse protecting those exterior lights, for shorts and have internal protection from the BCM (FET) to protect the circuit (internal of BCM)
BUT, thinking outside the box, think What If? they were pulling too much voltage from the circuit run. (Possible) it can be robbing needed power.
Hopefully, the Ford Tech will listen to you, and tell him what to look at, I am highly certain this is the problem. The Run/Start Relay and or Voltage / Ground issue at the Relay itself.
As this little relay, ties into ALL faults and Start/Driving Issues - The Common Between all of them that I was looking for.

Hope you didn't stay up all night trouble shooting this. If you in eastern Kansas around the KC area would like to buy you beer some time.
If you don't mind me asking where did you get your service info and what was the cost? I have Forscan, a test light and voltmeter for trouble shooting,(hope I never need it) just no service data or scope

 

[Rp930]

I FOUND IT, here is the Problem.

This is going to be a detailed post, so all can see and understand how I came to my solution.

In my wanting to learn what is actually powered in (Remote Start) I dug into the Power Distibution diagram and found the problem.

I am certain to 100% I have found the problem and its down to (1) little item.

I am attaching a PDF of this as well for clarity, I wanted to show color highlights, but it gets blurry when I insert image.

If you follow along the top of the page: (From Left)
Power From PCM Relay and note all modules being powered up to the Run/Start Relay
You are looking at the Remote Start Side of Power, note it will allow engine to run as you will have power coming off of the PCM Power Relay to the FCIM and the required Relays, Fuel Pump and Injectors for engine to start and run (Bare Minimum), this includes the Power Point Relays, so your power ports and whatever you have plugged in will have power.
So, this rules out, the item you had plugged in as the issue, unless you have lighting issues in addition to the no-start/driving, and it comes into play if it only does it (faults) when plugged into the power port, might be robbing power from the Run/Start Relay (I dont think this is causing any issues though) just a possible in this whole issue.

You also have power to the exterior lights off of that PCM Relay, so this also rules out the Lighted Grille as a cause until you apply a ground to the other side of the Run/Start Relay
Note: Where the Exterior Lighting is on that Power Feed, it's after the Run/Start Relay
Now it is possible, that the (Grille Lights) are pulling too much power and robbing power for the Run/Start Relay to have full voltage needed for it to operate.
It will not show up, until you add the Run/Start relay into the mix, by adding a power feed.
So, with this diagram I have proven that YES, a simple LED light being added to the Ranger may cause issues.

In Remote Start, you have power up to the (Run/Start) Relay but not past it. The Run/Start Relay circuit is completed via the Ignition Switch and BCM (Ground Signal)

Note the (2) Power Legs on the Run/Start Relay, (1) is for the BCM and (1) is for the rest of the modules, when the BCM provides the Ground, it allows the BCM circuit to complete, this also closes the power leg (Output) to the rest of the modules. (Within the relay)

Note: There is no Fuse between the PCM Power relay and the Run/Start Relay, it is direct power feed.

The Run/Start relay does not come in to play with Remote Start, it only comes into the circuit with the Ignition Switch - this is part of the PATS system (Anti-Theft) requires a Valid Key signal from the BCM and PCM and Key and PATS System

If you look past the Run/Start relay you will see all the modules that are getting power from that relay, note that the PCM, PSCM and ABS are receiving a power signal from that Run/Start Relay and telling the truck, (Key is in-Ignition) and switch is in (Run/Start) Position


So, the issue is the Run/Start Relay not being powered properly. (Possible Reasons Why)

1. Run/Start Relay itself is bad - (Needs Voltage and Ground Checks at the Relay) to ensure no abnormal readings or issue may return if you just replace it.

2. Bad Wire - Connection -(Power) Between the (2) relays PCM and Run/Start, I doubt this but cannot rule it out, as you are able to remote start, this should be good.

3. Bad Ignition Switch, not providing a valid signal to the BCM to allow a ground signal to the other side of the (Run/Start) relay. (To Complete the Circuit)

4. Bad wiring between the Ignition Switch and BCM

5. Bad BCM, not providing the Ground Signal to the Run/Start Relay

6. Bad Wire between the BCM and Run/Start Relay (Ground Signal)

7. Problem with the PATS system, not allowing the BCM to provide the Ground Signal to the Run/Start relay.

8. Grille Lights or Exterior Lighting, drawing too much power, creating a voltage loss at the Run/Start Relay

But when you take all of the Faults and Compare them to the Possible Problem, (Run/Start) Relay
You will find (Zero) specific codes directing you to it.

Now that I gave you all the possible issues, let's think outside the box here and play What-If
But first let's try to rule out some of the possibles.
1. You have (0) Codes related to PATS
2. You have (0) Codes related to BCM, except Communication
3. You have (3) Codes related to PCM, except Communication
4. You have (0) Codes related to Ignition Switch
5. You have (1) Code related to the ABS System except Communication

What you do have:

The PCM receives power a input from that Run/Start Relay, but since it is not Powered (Fully)
you see these Fault Codes on your List.
Brake Booster, Brake Switch Signal and Force Engine Shutdown

The ABS and PSCM receives power from the Run/Start Relay, but since they are not being powered fully you see the fault code Steering Wheel Position Sensor from the PSCM Module generating it and ABS Module Reporting it

and a long list of Communication Codes

HMM, now we have something to look at and play what-if?

Remember, I said to look at something that is switched, pressed actuated on a frequent basis for intermittent faults like this?
The Run/Start Relay - Is included in this little trick.

Right Now, the Run Start/Relay is Hard Faulted, and is not working, thus no start and most likely bad, not allowing both (2) circuits to complete.

Now for the What-If, this would explain the reason you have it running and driving it with all of the fault codes.
Let's say, the BCM provided the ground, and the Run/Start relay was only doing 1/2 of its job function.
It has 2
1. Provide the Ground, BCM to allow for the Ignition Key Start and remain powered when in Run.
2. The completed circuit above - will allow the Power Feed (Output) to the modules.

So, What IF?
The relay was only providing the Ground for the BCM to allow the truck to start with the key, but not closing the relay to allow power (output) to the modules. (Stuck Closed)
This will defiantly give you your fault tree of death.

So, you now have a Run/Start Relay not accepting power/ground (Dead) No Start with Key Condition and a (Sticking) Relay when you were able to drive it.

Now, the relay is just bad, or it has a voltage loss, (Not enough Voltage to Close) the Relay, from just a coincidence and a poor connection or Power Point (Plugged) in at the time of every fault or the Grille Lights.

I am ruling out all the modules that are powered by the Run/Start Relay, as they are individually fuse protected and I do not see anything that would take out the whole circuit.

So, check the Grille Lights and Wiring and Check Voltage Reading at Relay if good just replace the relay, you have a 50 AMP fuse protecting those exterior lights, for shorts and have internal protection from the BCM (FET) to protect the circuit (internal of BCM)
BUT, thinking outside the box, think What If? they were pulling too much voltage from the circuit run. (Possible) it can be robbing needed power.
Hopefully, the Ford Tech will listen to you, and tell him what to look at, I am highly certain this is the problem. The Run/Start Relay and or Voltage / Ground issue at the Relay itself.
As this little relay, ties into ALL faults and Start/Driving Issues - The Common Between all of them that I was looking for.

Looks like a solid diagnosis. I’m assuming the relay is in the fusebox? Looks like an easy check or two will prove you right.

 

[Markubis]

Disconnect all add-ons that have electrical connections and retest. I'm suprised (but not really) that the technicians didn't do this in their diagnostics or at least suggest it.

I had a very similar experience on a 2017 BMW R1200RT motorcycle with CAN bus problems after aftermarket fog lights installed. An isolation relay was needed but not used. Once the circuit was returned to stock the mysterious CAN bus problems went away.

Because most technicians nowadays are useless hacks that don't know how to diagnose an issue. They look for a code and do what it says. That's it. No actual analytical thinking goes on anymore.

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