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How to: Ford Explorer Fuel Pump Electrical Procedure

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2000StreetRod

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Year, Model & Trim Level
00 Sport FI, 03 Ltd V8
Background

This procedure was written for a 2000 Explorer Sport with SOHC V6. The wiring should be very similar for 1998 thru 2000 models.

The energizing of the Fuel Pump Relay is controlled by the PCM. If the PCM does not have power then neither will the Fuel Pump Relay.

The Inertia Fuel Shutoff (IFS) switch (located next to the front passenger kick panel) prevents the fuel pump from receiving power after a collision.

The main power to the Fuel Pump Relay comes from Fuse 9 (20 amps) in the Battery Junction Box. The PCM energizes the Fuel Pump Relay for a few seconds when the Ignition Switch is turned to On and when the Ignition Switch is turned to Start. Two persons may be required to accomplish some of the steps. One to turn the ignition key and the other to perform a voltage measurement.

The Haynes Repair Manual incorrectly states that the PCM will energize the fuel pump relay as long as pulses from the Camshaft Position Sensor (CMP) indicate that the crankshaft is rotating. Actually, the PCM monitors pulses from the Crankshaft Position Sensor to determine if the crankshaft is rotating. The PCM uses the pulses from the Camshaft Position Sensor to determine if cylinder 1 is on the compression or exhaust stroke.

Procedure

1. Turn Ignition Switch to On
Does "CHECK ENGINE" illuminate?
Yes: Go to next numbered step
No: Perform the PCM Power Procedure

2. Do you hear the Fuel Pump run for a few seconds when Ignition Switch is switched to On?
Yes: If desired perform the Fuel pressure test procedure
No: Go to next numbered step

3. This check isolates between a failure in the power path to the fuel pump and the PCM controlled energizing of the fuel pump relay.
a. Remove the fuel pump relay in the Battery Junction Box
b. Install a jumper between relay socket contacts 3 and 5.
c. Switch ignition to ON. Does fuel pump should run continuously?
Yes: Failure is due to fuel pump relay or PCM control of relay. Go to step 9.
No: Failure is due to bad fuel pump, power path to fuel pump or power path from fuel pump to chassis ground. Go to next numbered step

4. Is Inertia Fuel Shutoff (IFS) switch set (button pushed in)?
Yes: Go to next numbered step
No: Depress IFS reset button and repeat step 2 above

5. Is Fuse 9 (20 amps) in the Battery Junction Box good?
Yes: Go to next numbered step
No: Replace fuse and repeat step 2 above

6. Disconnect Fuel Pump/Sending Unit electrical connector (C311) located on the inside of the left frame rail in front of Fuel Tank.

7. Is the resistance from female C311, Pin 7 (black wire) to ground less than 1 ohm?
Yes: Go to next numbered step
No: Clean/tighten the ground connection (G204) located under left side of Instrument Panel behind Kick Panel. Reconnect electrical connector and repeat step 2 above.

8. Is the voltage at female C311, Pin 6 (pink/black wire) battery voltage when Ignition Switch is switched to ON?
Yes: Remove/replace fuel pump
No: Check wiring for breaks from connector to Inertia Fuel Shutoff switch

9. Remove jumper and Swap Fuel Pump Relay in the Battery Junction Box with the Rear Wiper Down Relay in the Battery Junction Box and repeat step 2 above.

10. Make sure PCM connector bolt is snug (do not overtighten).

11. Remove PCM connector and see if pin 80 is pushed back.
 



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'02 fuel delivery issues

I did try searching, but I didn't come up with much. I have a V-6 with auto that suddenly won't start. Starting fluid sprayed into air filter gets it running, but only a few seconds. Tried to figure if my fuel pump was running, but don't hear it at all. The Chilton's manual I have is useless for any electrical engine/fuel issue problems, so I can't even be sure which is the FP relay, or the fuse. Did check the reset switch in the kick panel, and it's okay.

Does anyone have a schematic that shows which is the FP relay, and which fuse controls it? Any info that would allow me to start tracking it down would be appreciated. Thanks
 






Owner's Guide

Your Explorer Owner's Guide should have drawings of the passenger compartment fuse panel, the power distribution box relays and fuses and list what they are for. Mine are described in the Roadside Emergencies section.
 






I changed out the pump assembly and fuel filter and still no pump action? I have 12 V to the pump through the pink and blk wire but I have not checked for ground. I guess I replasced the pump for nothing. The one I took out was the original as it was dated and when I hooked it up directly to a battery it works. I still dont hear the pump kicking in?
any info will be helpful
 






fuel pump relay removal?

Replacing the fuel filter will probably extend the life of the newly installed fuel pump so it wasn't a waste of time and money.

A check that I should add to the procedure is to defeat the PCM control of power to the fuel pump. That allows easy testing of the electrical path from the fuel pump relay.

1. Remove the fuel pump relay and install a small flat blade screw driver into contact 5 of the relay socket in the battery junction box.
2. Connect the positive clip of a battery charger to the shaft of the screwdriver.
3. Connect the negative clip of the battery charger to chassis ground.
4. Energize the battery charger.

The fuel pump should run continuously as long as power is supplied. If it doesn't then the inertia fuel shutoff is tripped, the fuel pump is bad, the electrical path from the fuel pump relay to the inertia fuel shutoff is open, the electrical path from the inertia fuel shutoff to the fuel pump is open, or the electrical path from the fuel pump to chassis ground is open.

If the fuel pump runs when above steps are performed then the problem is with the fuse 9 in the battery junction box, fuel pump relay, the crankshaft position sensor, or the electrical path from the PCM to the fuel pump relay. Also, if there is no power to the PCM the fuel pump relay will not energize.
 






The fuel pump relay is working and I also switched it with another relay that I know was good. The inertia fuel shutoff looked good and the 12V was getting to it. When I checked the 12V to the harness that connects to the new fuel pume it was there at the pink/blk wire. How do I know which is contact 5 ? and do I need the key on to try this? Does th fuel pump only get its ground throught he Blk wire? Can I run a ground from the fram right to the fuel pump ?
Thank you for your help
 






I looked at my owners manuel and it reads that the #9 fuse in the engine box is a 20A**
power point #2
 






relay contact numbers

The fuel pump relay is working and I also switched it with another relay that I know was good. The inertia fuel shutoff looked good and the 12V was getting to it. When I checked the 12V to the harness that connects to the new fuel pume it was there at the pink/blk wire. How do I know which is contact 5 ? and do I need the key on to try this? Does th fuel pump only get its ground throught he Blk wire? Can I run a ground from the fram right to the fuel pump ?
Thank you for your help

On the fuel pump relay next to the pins are stamped their associated numbers. Match the relay pin with its socket contact. If you have battery voltage to the fuel pump connector then there is no problem with the path prior to it or the relay energizing path. Which fuel pump connector are you referring to? Is it the one shown below?
FPConnector.jpg

If so then the problem is from the connector to the pump or from the pump to the chassis ground. The chassis ground (G204) is located under the lest side of the instrument panel behind the kick panel. There are numerous other components spliced into the wire going to the ground. If it was bad other things besides the fuel pump would not work (power seat motors, power door locks, door ajar lights, vanity lamps, safety belt warning light, etc.). Yes, you can run a chassis ground wire directly to the fuel pump black wire. Maybe the connector is bad.
 












On the fuel pump relay next to the pins are stamped their associated numbers. Match the relay pin with its socket contact. If you have battery voltage to the fuel pump connector then there is no problem with the path prior to it or the relay energizing path. Which fuel pump connector are you referring to? Is it the one shown below?
View attachment 77265
If so then the problem is from the connector to the pump or from the pump to the chassis ground. The chassis ground (G204) is located under the lest side of the instrument panel behind the kick panel. There are numerous other components spliced into the wire going to the ground. If it was bad other things besides the fuel pump would not work (power seat motors, power door locks, door ajar lights, vanity lamps, safety belt warning light, etc.). Yes, you can run a chassis ground wire directly to the fuel pump black wire. Maybe the connector is bad.

Everything else electricel works well on the truck. I have had on ocasion for no reason the alarm go off/ or the door locks act up a bit? Yes it is looks like the connector in your pic , only mine runs right on top of the rail to the tank and the harness from the new pump unit pluges right in to it. That is where I read the 12V to the pump on the pink/Blk hot wire. But I havent checked the ground yet?
Thank you again
 






PCM Relay part number??

I have looked high and low for the Part# for the PCM relay on a 98 4.0 SOHC and cannot find one! Anybody know the number? Or will any generic 30a 5 prong relay work?
Thank for any help.
Chef Duane
:usa:
 












I think Standard Motor Products Part Number RY116T should be suitable. If you want to get an OEM replacement you can call the dealer.


The RY116T was a cross reference for the OEM. Seems to be just fine.
Got one at O'Reilly. Thanks!
Chef Duane
 






Replacing the fuel filter will probably extend the life of the newly installed fuel pump so it wasn't a waste of time and money.

A check that I should add to the procedure is to defeat the PCM control of power to the fuel pump. That allows easy testing of the electrical path from the fuel pump relay.

1. Remove the fuel pump relay and install a small flat blade screw driver into contact 5 of the relay socket in the battery junction box.
2. Connect the positive clip of a battery charger to the shaft of the screwdriver.
3. Connect the negative clip of the battery charger to chassis ground.
4. Energize the battery charger.

The fuel pump should run continuously as long as power is supplied. If it doesn't then the inertia fuel shutoff is tripped, the fuel pump is bad, the electrical path from the fuel pump relay to the inertia fuel shutoff is open, the electrical path from the inertia fuel shutoff to the fuel pump is open, or the electrical path from the fuel pump to chassis ground is open.

If the fuel pump runs when above steps are performed then the problem is with the fuse 9 in the battery junction box, fuel pump relay, the crankshaft position sensor, or the electrical path from the PCM to the fuel pump relay. Also, if there is no power to the PCM the fuel pump relay will not energize.

I tried doing this but I still go nothing. I hooked a metet to the harness at the fuel pump across the blk and the bl/pink wire and got 12V when I read the ground to the body it read good this was with the pump not connected. but when I turn the key on witht the pump hooked back up I loose my 12V ?
So I guess Im not getting enough power to run the pump. Now I need to figuer out why?
Thank You for your help
 






Is there a way to hook a bettery right to the 2 wires that run from the inertia switch or can I just jump those 2 wires together and bypass the switch and see if if that works. I dont want to do any damage to the electricl system more then waht ever is going on now? I think I said that I hooked the old fuel pump directly up to a battery and it still worked so I guess what ever was going on with the old pump is now going on with the new one.
 






measure for continuity

To me it is unlikely that the power to the connector is insufficient to power the pump. I suggest that you measure the resistance between the blk and the bl/pink wires on the pump side of the connector with the connector disconnected. There may be a broken wire or bad connection in that path. If the resistance is reasonable (probably a few ohms) then apply battery power to the same pins and see if the pump runs.
 






the new pump I have in the tank now is good. the new harness was already attched to the new pump when I bought it. I see some ground straps from the chasey to the body and they are not clean looking. whould this affect the ground to the pump or is the blk wire in the harness the only place the pump unit gets it ground from? I am not use to these plastic tanks. The old trucks had a grand strap right from the pump and metal tank to the chassey. can I cut the 2 wires going into the inetia switch and hook a battery to it to put power to the pump. I even took the old pump unit that I know was still good now and pluged it back in to the harness on the rail and I cant even get it to power up when I turn the key on.
Thank you for you help
 






please be specific

If power is applied to the fuel pump side of the connector pins for the blk and the bl/pink wires does the pump run (yes or no)?

On the non-pump side of the connector what is the resistance to chassis ground of the pin with the blk wire?
 






Thank you for your reply. I will have to recheck these in the morning as it is to dark for me to see . Vision ant what it use to be!
Thank you for your time .
 



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If power is applied to the fuel pump side of the connector pins for the blk and the bl/pink wires does the pump run (yes or no)?

On the non-pump side of the connector what is the resistance to chassis ground of the pin with the blk wire?

The new fuel pump I put in runs when I hook my charger to the 2 wires they did away with the pin/blk combo and olnlhave a red wire and a black wire so that is what I hooked up to and it runs.
On the non-pump side I had my meter on ohms and I got 000.4 when I read the meter hooke to the chassie
 






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