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navsnipe

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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.
I don't disagree but all techs are handcuffed by guided fault finding. They have to follow the guidelines and procedures the manufacturer sets for troubleshooting and warranty coverage otherwise they don't get paid. I've found a lot of the good troubleshooters move on to independent shops or open their own.
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NotBudule

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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.




Run-Start Relay.jpg
Damn it man ,you stole my post ! , I was up all night and came to the same conclusion, even had a diagram like yours (mine was a little better as I tried to dumb it down for the masses) but yeah , you beat me to it... Unless your wrong I mean...
 

Rp930

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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.
I wouldn’t say most at all. The problem is while the best technician is diagnosing a tough problem on straight time the dummy next to him is flat rating a maintenance and bringing home a bigger paycheck. The flat rate system is flawed.
 

dtech

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Damn it man ,you stole my post ! , I was up all night and came to the same conclusion, even had a diagram like yours (mine was a little better as I tried to dumb it down for the masses) but yeah , you beat me to it... Unless your wrong I mean...
wasn't April 1 a few weeks back ?
 


dtech

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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.
Give em some credit, they didn't replace the engine as one poster reported a ways back that the torque converter was replaced when his EGR sensor failed.
 

Max Crafter

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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.
I'm not sure how many hours AirlineTech put into that synopsis, but as a consumer, are you even willing to pay him shop rate to do that work behind the scenes?
That's probably why many shops are parts changers.
A broken clock is right at least twice a day and the law of averages is probably in the shops favor to change the part the trouble code points to.
 

P. A. Schilke

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I'm not sure how many hours AirlineTech put into that synopsis, but as a consumer, are you even willing to pay him shop rate to do that work behind the scenes?
That's probably why many shops are parts changers.
A broken clock is right at least twice a day and the law of averages is probably in the shops favor to change the part the trouble code points to.
Hi Max,

The Dealer level shop manual (on line) had quite detailed diagnostic flow charts to diagnose the trouble codes, but it requires a few things, Time, the ability to read, and the determination to follow the flow charts to name a few. Parts changing is just a short cut and most likely wrong much of the time. Dealer service manager pressure is sure on the techs to "do something and get the truck out the door".

Best,
Phil
 

Markubis

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I'm not sure how many hours AirlineTech put into that synopsis, but as a consumer, are you even willing to pay him shop rate to do that work behind the scenes?
That's probably why many shops are parts changers.
A broken clock is right at least twice a day and the law of averages is probably in the shops favor to change the part the trouble code points to.
Agreed, but when the vehicle keeps coming back and all you do is look for a code then there's a serious problem with their mechanic skills.
 

seasprite

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Hi Max,

The Dealer level shop manual (on line) had quite detailed diagnostic flow charts to diagnose the trouble codes, but it requires a few things, Time, the ability to read, and the determination to follow the flow charts to name a few. Parts changing is just a short cut and most likely wrong much of the time. Dealer service manager pressure is sure on the techs to "do something and get the truck out the door".

Best,
Phil
They don't call it the parts cannon for nothing
?
 
OP
OP

ppfd

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Airline,
Thank you!
You have done more for free then the ford garage is doing while getting paid.
And I get it, 8-10 hours on this nonsense when they could be doing a few simple jobs and making more money most likely.
So, how do I approach the garage about this? Print off the posts and give them to the manage and mechanic?
I just see them going in the trash when I leave.
And to answer a question from earlier, when I do open the door, lights come, dash lights up. And when the truck will key start the fuel pump kicks on, etc.

Dealer won’t even look at it till next week, and he gave me some bullshit about a loaner car.
I’m going to email/call the gal that opened my case and start the LL proceedings next week. I’m racking up miles on my GFs car and she’s putting miles on her Jeep when none of that should be happening, this is 10 times at least in close to 3 months now.
 

9zero1790

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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.




Run-Start Relay.jpg
Bravo Zulu Sir!
1681584141453.webp
 
 








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