Ranger Starting issue - Not the fuel pump

[airline tech]

TJC is referencing my Troubleshoot Steps and if I am correct the Tech has found an issue here, no power at one of the contacts, If I had to guess the issue is highly likely on the contact that was pushed down.
The relay box needs to be opened up and inspected to confirm, however if he is not seeing a ground from the PCM then it is possible the PCM or Ground Wire is bad.

Pull the FP Relay out (if using step 1)

Key (ON) and with meter in Volts DC
Ref the Diagram Above:

Note: Since I am not sure (100%) which Terminals are what (Location)
I do know that the (2) vertical contacts are 30 & 87 (the center one is 87a)
The Horizontal ones are Contacts 85 & 86

But with that in mind should be:
Pin 87 = Top
Pin 30 = Bottom
Pin 85 = Right
Pin 86 = Left

The vertical & horizontal may be opposite sides of each other (so swap them if needed)

The main point is with Key (ON) you should be getting power to (2) contact pins
Pins: 30 & 86

Relay Control:

Pin 30 = Always Powered
Pin 86 = Powers with Key (ON) and the EEC Relay Closes (Switched Power)

With meter set to Volts DC:
Red Lead to Pin 30
Black Lead to (Neg) Batt Terminal or Body Ground

Repeat for Pin 86:

You should be getting 12-Volts, note if no voltage swap to the opposite side (vert or Harz) in case my Top/Bottom and Left/Right are backwards.
On BOTH Contacts - 30 & 86

If no power on pin 30 - the issue is in the relay box or fuse
if no power on pin 86 - the issue in with the EEC/PCM power relay or wiring
This is where is gets deep into a T/Shoot as we do not know if the Wiring/ PCM Power Relay / or the EEC itself has fried.
So, we need to do a more detailed T/Shoot - If this is the case as there are deeper steps to take for this.

If you have power on both pins 30 & 86,
Then you have an issue with the FP Relay itself or relay box
To T/Shoot this, we need to disconnect the battery, the EEC Connector and the Fuel Inertia Switch and use the meter (ohms) scale and resistance check the wires
For the wire runs for Pins 87 & 85 and pull apart the Relay box and check for broken wire feeds coming from the FP Pump relay contacts - with a close inspection of the pin that was pushed down.

Relay Control (Explained)
You have constant power on Pin 30
You have (switched power) on pin 86 coming from the PCM Power Relay

When you switch the ignition switch to Run a Ground is provided to Pin 85 (From The PCM)

So, you now have (Current Flow) through Pin 86 and Pin 85 - This Current Flow creates a Magnetic Field within the (Coil) of the relay, that magnetic field pulls the (switch) over a creates a path for the current flow from Pin 30 to 87.

However, there are factors in play as to when the PCM will supply the Ground to the relay, as the PCM needs to see ignition, injectors powering (pulsing)

But with you by-passing the circuit (control) already I am certain the issue is Power, and it lies on one of the 3 contact pins at the relay.
Most probable is Pin 30 or 86 as if either of those do not have power (the fuel pump cannot run)
More precisely with your jumper test I am going with Pin # 30 has the issue and is not getting voltage.

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[airline tech]

Here is a typical relay. Disregard the bottom circle. It is the connector.

Notice the "To Positive Trigger source", That is the 12V source for the coil, The negative side says "To Ground". In between those 2 pins is an electro-magnet. It energizes and becomes a magnet when 12v is applied from the trigger source, in your case the ignition switch. When this happens it completes the circuit, 12v floes from the battery through the relay out to the device (your fuel pump) then completes the circuit ground back to your battery negative terminal completing the circuit. The body of your truck is one big negative wire. The negative terminal of the battery is connected directly to the chassis in your truck.

If any of those wires are open (broke), your fuel pump isn't going to run.

With one slight difference the Fuel Pump relay is a 5-Pin relay (Pin 87A) this is the power source for the Fuel Pump (2-Second) Prime, and I have not brought that into the equation as with the jumper (by-pass) that has been done, eliminated that pin. Jumper was no help, and it should have powered the pump to run.

 

[Digbird1]

The 2nd mechanic I had over that checked that, measured with a meter and it was clicking or whatever it supposed to do. And the relay as also been swapped out with a different relay so I don't think that's the issue. I've also ran a jumper wire from the + to - pins into the module the relay plugs into with no luck.

 

[Digbird1]

Also let me give you more background
I had a 2nd mechanic over for an hour and he took the new fuel pump out and our the old one back in and then used a voltmeter to check the fuses and relays in the distribution box and he said everything looked good, Then it started to rain and he wasn't comfortable taking the distribution box apart. The third mechanic sounded good in the Ad but was a total asshole.
He didn't want me to watch him work, then 30 minutes into working he txted me and said both fuel pumps are bad as well as the starter. So I said that;s enough, The fuel pumps have both been tested as good. Then he got hostile and forced me to pay him to pay him $150 for coming over and doing nothing productive for 30 minutes. Now the shop tells me the problem is in the distributiion box wiring. Hello I've said that for a month. To be fair they are just dealing with this objectively.
But just cost me another $200. Now the tech left a note that fixing the issue could take 4-6 hours of labor. And if the distribution box or harness is bad then that's another $300-$700.
So at this point I am at a loss.
The truck is in great shape overall, 150,000 miles and wasn't driven much at all for 15 years when I worked in NYC.
But I have to be practical. I don't know if it's worth sink another $600-$800 in labor if it takes 4 hours for the tech to track down the issue. But also it has no resale value as is.

 

[Digbird1]

How l

TJC is referencing my Troubleshoot Steps and if I am correct the Tech has found an issue here, no power at one of the contacts, If I had to guess the issue is highly likely on the contact that was pushed down.
The relay box needs to be opened up and inspected to confirm, however if he is not seeing a ground from the PCM then it is possible the PCM or Ground Wire is bad.

Pull the FP Relay out (if using step 1)

Key (ON) and with meter in Volts DC
Ref the Diagram Above:

Note: Since I am not sure (100%) which Terminals are what (Location)
I do know that the (2) vertical contacts are 30 & 87 (the center one is 87a)
The Horizontal ones are Contacts 85 & 86

But with that in mind should be:
Pin 87 = Top
Pin 30 = Bottom
Pin 85 = Right
Pin 86 = Left

The vertical & horizontal may be opposite sides of each other (so swap them if needed)

The main point is with Key (ON) you should be getting power to (2) contact pins
Pins: 30 & 86

Relay Control:

Pin 30 = Always Powered
Pin 86 = Powers with Key (ON) and the EEC Relay Closes (Switched Power)

With meter set to Volts DC:
Red Lead to Pin 30
Black Lead to (Neg) Batt Terminal or Body Ground

Repeat for Pin 86:

You should be getting 12-Volts, note if no voltage swap to the opposite side (vert or Harz) in case my Top/Bottom and Left/Right are backwards.
On BOTH Contacts - 30 & 86

If no power on pin 30 - the issue is in the relay box or fuse
if no power on pin 86 - the issue in with the EEC/PCM power relay or wiring
This is where is gets deep into a T/Shoot as we do not know if the Wiring/ PCM Power Relay / or the EEC itself has fried.
So, we need to do a more detailed T/Shoot - If this is the case as there are deeper steps to take for this.

If you have power on both pins 30 & 86,
Then you have an issue with the FP Relay itself or relay box
To T/Shoot this, we need to disconnect the battery, the EEC Connector and the Fuel Inertia Switch and use the meter (ohms) scale and resistance check the wires
For the wire runs for Pins 87 & 85 and pull apart the Relay box and check for broken wire feeds coming from the FP Pump relay contacts - with a close inspection of the pin that was pushed down.

Relay Control (Explained)
You have constant power on Pin 30
You have (switched power) on pin 86 coming from the PCM Power Relay

When you switch the ignition switch to Run a Ground is provided to Pin 85 (From The PCM)

So, you now have (Current Flow) through Pin 86 and Pin 85 - This Current Flow creates a Magnetic Field within the (Coil) of the relay, that magnetic field pulls the (switch) over a creates a path for the current flow from Pin 30 to 87.

However, there are factors in play as to when the PCM will supply the Ground to the relay, as the PCM needs to see ignition, injectors powering (pulsing)

But with you by-passing the circuit (control) already I am certain the issue is Power, and it lies on one of the 3 contact pins at the relay.
Most probable is Pin 30 or 86 as if either of those do not have power (the fuel pump cannot run)
More precisely with your jumper test I am going with Pin # 30 has the issue and is not getting voltage.

how long would you estimate it would take a mechanic that knows what he's doing to do this?

 

[airline tech]

How l

how long would you estimate it would take a mechanic that knows what he's doing to do this?

So, if I understand where the mechanic is at - Power Wise, he has voltage on pin 86 and he is getting a ground from the PCM (The Click)
That is good news as you have just eliminated 1/2 of the Troubleshoot - Coil side of the relay is GOOD.

So now we back up to the 2 Pins you jumped, (with one of them being) the contact that was pushed down.
So, with the info I have from you - thus far.
The relay box needs opened up - and those 2 wires need inspected at the point where they connect to the relay box (underside)
One of those wires is the Power Feed (PIN 30) Battery Voltage, feeding the Relay
and
The other (Pin 87) is feeding the Fuel Pump
One of these 2 wires are cut/broken, and I highly suspect it is the one that was pushed down.
Sure, you can see the contact but is the wire still attached to it?
Sometimes wiring diagrams do not depict actual wire pins as they are actually laid out on the relay center - so unsure with 100% certainty which pin is 30 or 87. (Top or Bottom) the wiring diagram has Pin 30 on (TOP) but the relay has it on the (Bottom)

So, IF the mechanic is getting voltage on one of these pins with key (on) then the issue is with the other pin (feeding the Fuel Pump)
This is where checking for power at the (Fuel Inertia) Switch will show if Pin 87 is good and allowing power through it.

Either way, open the relay box and inspect the wires, and repair as needed, it may take some digging to find the correct P/N for the contact (like the one that was pushed down) to replace it.
as I suspect the wire is broken off the end of the contact pin/socket.
Open & Inspect allow 1/2-hour, wire repair & research is going to take some time as you have to find a pin/socket that will replicate the OE and lock itself into the box.

It does sound like the current mechanic is on the right track, and this will be a simple repair of the wire in the relay box.

 

[Digbird1]

So, if I understand where the mechanic is at - Power Wise, he has voltage on pin 86 and he is getting a ground from the PCM (The Click)
That is good news as you have just eliminated 1/2 of the Troubleshoot - Coil side of the relay is GOOD.

So now we back up to the 2 Pins you jumped, (with one of them being) the contact that was pushed down.
So, with the info I have from you - thus far.
The relay box needs opened up - and those 2 wires need inspected at the point where they connect to the relay box (underside)
One of those wires is the Power Feed (PIN 30) Battery Voltage, feeding the Relay
and
The other (Pin 87) is feeding the Fuel Pump
One of these 2 wires are cut/broken, and I highly suspect it is the one that was pushed down.
Sure, you can see the contact but is the wire still attached to it?
Sometimes wiring diagrams do not depict actual wire pins as they are actually laid out on the relay center - so unsure with 100% certainty which pin is 30 or 87. (Top or Bottom) the wiring diagram has Pin 30 on (TOP) but the relay has it on the (Bottom)

So, IF the mechanic is getting voltage on one of these pins with key (on) then the issue is with the other pin (feeding the Fuel Pump)
This is where checking for power at the (Fuel Inertia) Switch will show if Pin 87 is good and allowing power through it.

Either way, open the relay box and inspect the wires, and repair as needed, it may take some digging to find the correct P/N for the contact (like the one that was pushed down) to replace it.
as I suspect the wire is broken off the end of the contact pin/socket.
Open & Inspect allow 1/2-hour, wire repair & research is going to take some time as you have to find a pin/socket that will replicate the OE and lock itself into the box.

It does sound like the current mechanic is on the right track, and this will be a simple repair of the wire in the relay box.

Thanks, the issue is that my truck is parked in the shop's lot.
The 2nd mechanic got these readings.
The shop tech quoted 4-6 hours to check the wiring, But to be fair he had only isolated that the distribution box is the issues as they got the ranger running for about 10 seconds ..again by manually powering the pump.
At this point I need to make a decision and continuing with the shop as if it takes them another 3 hours it's a total bill of $600 at least.

 

[airline tech]

This is an example pic of the back side of a fuse panel, not for your truck.
This, needs accessed to view the wires on the back side of the relay center and inspect the wires running to the Fuel Pump Relay.
The Front side of this box - is the fuses.

I suspect you have a broken wire at the terminal end (Socket) and the wire is not attached or that wire is broken somewhere within the box
Being that as of now the current mechanic has isolated it down to the relay box.

Example Pic: Yours is similar setup

 

[Digbird1]

OK, So I towed it to a nearby shop I trust. Then did troubleshooting on it for four hours. They found that everything fuel pump relay wise in the distribution box is getting power and ground, and that the fuel pump is getting power. But there's a big loss of fuel pressure between the tank and the fuel rail in the engine compartment. At this point the tech was stumped. The shop was cool enough not to charge me but I still need to find someone to figure it out and fix it. Any ideas or advice?
Thanks again!

Dan

 

[RangerBill]

OK, So I towed it to a nearby shop I trust. Then did troubleshooting on it for four hours. They found that everything fuel pump relay wise in the distribution box is getting power and ground, and that the fuel pump is getting power. But there's a big loss of fuel pressure between the tank and the fuel rail in the engine compartment. At this point the tech was stumped. The shop was cool enough not to charge me but I still need to find someone to figure it out and fix it. Any ideas or advice?
Thanks again!

Dan

Earlier you said that a mechanic got it to run by powering the fuel pump directly. Now, another mechanic says the fuel pump is running but delivers no fuel to the engine (no fuel pressure). A good mechanic should be able to figure this out. I would take it to a reputable mechanic. This will cost you less in the long run. You need to find someone who can troubleshoot.

 

[RangerBill]

You basically need a mechanic who knows how to use a fuel pressure gauge and a voltmeter and read electrical diagrams. It should not be that difficult to find the problem.

 

[Digbird1]

This is a very reputable shop, They have done other work for me and did a great job at a great price. Two mechanics have gotten it to start by applying ground directly to the pump jumping/bypassing whatever electronics. The mechanic did not say the fuel pump wasn't outputting fuel, He said that is is putting out fuel, but either at a low pressure, or there's a loss of pressure between the tank and the engine.

 

[Digbird1]

They did use a fuel pressure gauge and said that at the fuel rail the pressure is waay below what it needs to be, They also troubleshooted the distribution box so they know how to use a fuel pressure gauge and a voltmeter.

 

[RangerBill]

This is a very reputable shop, They have done other work for me and did a great job at a great price. Two mechanics have gotten it to start by applying ground directly to the pump jumping/bypassing whatever electronics. The mechanic did not say the fuel pump wasn't outputting fuel, He said that is is putting out fuel, but either at a low pressure, or there's a loss of pressure between the tank and the engine.

A good mechanic would be able to figure out what is causing the loss of fuel pressure. If there is some fuel pressure, the truck should at least start and idle. What is the fuel pressure reading at the fuel rail?

 

[Digbird1]

Don't bother commenting anymore Bill if you are just going to insult the shop and not be helpful or constructive.

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