testing fuel pump driver module on 2008 f350

#Testing fuel pump driver module on 2008 f350 code#

It can also verify that the fuel pump relay contacts are closed and there is a B+ supply to the fuel pump relay.

With the pump on and the FPDM circuit high, the PCM can verify that the FP power circuit from the fuel pump relay to the FPDM splice is complete. With the pump running, voltage is now being supplied from the pump relay to the FP power and FPDM circuits. This also confirms that the FP power or FPDM circuits are not shorted to power. The PCM is also able to verify that the FPDM circuit and the FP power circuit are complete from the FPDM splice through the pump to ground. With the pump off, this voltage is pulled low by the path to ground through the fuel pump. When starting the engine, the PCM sends a low current voltage down the FPM circuit. Some inputs that it uses are the fuel rail pressure sensor, throttle angle engine temperature etc. The Powertrain control module and inputs to the powertrain control module will determine how fast the fuel pump driver module will run. Ford uses a pulse width modulated Fuel Pump Driver Module (FPDM or fuel pump control unit) to control the fuel pump speed. On these vehicles, the fuel system is a bit different. Click here to chat live with a Ford Mechanic. But first, I will explain how the fuel pump operates. From there, I can pull codes and read live data using my scanner. Next step was to plug into the 16 pin OBD2 diagnostic connector located under the dash. I was quickly able to confirm the engine has spark by verifying that the check engine light goes off while cranking the engine over and also by using my spark tester installed into the ignition coil.

#Testing fuel pump driver module on 2008 f350 code#

There was a diagnostic trouble code of P0191 and P1233.

Upon checking, the truck had spark but no fuel pressure when cranking. Customer stated they were in the middle of a car wash and the engine stalled out and would not restart. Recently, we had a 2004 ford f150 with a 5.4-liter engine towed into the shop.