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Fuel Pump Diagnosis - Test Jumper

  • Thread starter Thread starter BlueGT2k
  • Start date Start date Jul 8, 2021
B

BlueGT2k

New Member
Jun 15, 2003
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1
Fort Wayne, IN
Jul 8, 2021
#1
  • Jul 8, 2021
  • #1
Trying to diagnose a fuel delivery problem on my 2000 GT. The car was idling in the driveway and unexpectedly stalled with no restart. The engine turns over, but had a low fuel pressure code CEL and couldn't get it to start again. There was no sputtering or sign of impending stall condition before the motor just stopped running.

To me, this doesn't seem consistent with a failed/failing fuel pump, so trying to rule out the Fuel Pump Relay (part of CCRM), OR Fuel Pump Drive Module (FPDM) before concluding fuel pump replacement is needed.

Does anyone have wiring diagrams for the FPDM and Fuel Pump pigtail connectors? Trying to determine if there is a safe way to jumper the fuel pump to determine if it is operational and backtrack power signal. I have confirmed power at the inertia switch, so doesn't seem to be the CCRM.

Any advice/recommendations are appreciated.
 

weendoggy

5 Year Member
Jan 14, 2019
198
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Aptos, CA
Aug 4, 2021
#2
  • Aug 4, 2021
  • #2
BlueGT2k said:
Trying to diagnose a fuel delivery problem on my 2000 GT. The car was idling in the driveway and unexpectedly stalled with no restart. The engine turns over, but had a low fuel pressure code CEL and couldn't get it to start again. There was no sputtering or sign of impending stall condition before the motor just stopped running.

To me, this doesn't seem consistent with a failed/failing fuel pump, so trying to rule out the Fuel Pump Relay (part of CCRM), OR Fuel Pump Drive Module (FPDM) before concluding fuel pump replacement is needed.

Does anyone have wiring diagrams for the FPDM and Fuel Pump pigtail connectors? Trying to determine if there is a safe way to jumper the fuel pump to determine if it is operational and backtrack power signal. I have confirmed power at the inertia switch, so doesn't seem to be the CCRM.

Any advice/recommendations are appreciated.
Click to expand...
(7) Red/Blk & (6) Brn/Pnk should be the colors in the plug to the pump itself. You should be able to disconnect the pump/PCM harness at the pump and use a jumper for Bat + and Bat - to those and see if the pump works. Basically a bench test of the pump. Be sure to disconnect the connection prior to testing.
 

manicmechanic007

5 Year Member
Sep 26, 2017
2,531
713
143
Roy, Utah
Nov 4, 2021
#3
  • Nov 4, 2021
  • #3
The other parts never fail
Or almost never fail
Replace the fuel pump
They die exactly like that
 
S

scottswierenga

New Member
Mar 23, 2022
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0
1
Bellevue, Nebraska
Mar 23, 2022
#4
  • Mar 23, 2022
  • #4
weendoggy said:
(7) Red/Blk & (6) Brn/Pnk should be the colors in the plug to the pump itself.
Click to expand...

I have been looking for a diagram that would show me which pin/wire is what, within the connector. To this point I have not found what I am looking for, and your statement is the closest I have come so far.
I want to Ohm check the motor and see if it registers any resistance to attempt to determine if the motor had Open Windings.

Do you know which pin is 6 & 7 in the connector, as viewed when the connector is unplugged?
 

Noobz347

Stangnet Facilities Maint Tech... Er... Janitor
Admin Dude
Jan 4, 1985
42,987
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234
Box behind Walmart
Mar 24, 2022
#5
  • Mar 24, 2022
  • #5
manicmechanic007 said:
The other parts never fail
Or almost never fail
Replace the fuel pump
They die exactly like that
Click to expand...
^this
 
N

n0v8or

10 Year Member
Aug 23, 2003
604
8
39
Rhode Island
Apr 9, 2022
#6
  • Apr 9, 2022
  • #6
When I suspected a bad fuel pump on my 2003, I made up a jumper cable so I could measure the pump voltage and current during cranking.
Here is a drawing looking into the connectors:
 

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