Ford focus fuel pump driver module problems

#FORD FOCUS FUEL PUMP DRIVER MODULE PROBLEMS DRIVER#

ItвЂ™s probably quite a bit of current, 10 amps or more maybe, so an ordinary current meter might not work and could be damaged if wired up in-line. IвЂ™d be inclined to measure the current flow in the power wire going to the pump to assess if the ground is being connected or not. It would look like the pump is getting power at its 12 volt input, but in fact the ground isnвЂ™t being connected. This could indeed be confusing to debug from the comments in the posts above. Verify continuity and pin fit at related electrical connectors.

#FORD FOCUS FUEL PUMP DRIVER MODULE PROBLEMS DRIVER#

Circuits between the Driver module and pump could be compromised.

5% equals 10% pump request, 50% command is 100% on the pump, remember the pressure control is fully variable) (Signal is a duty cycle 5-50 percent is a valid on request. IF the COM circuit (blk/wt) circuit is open, the FPDM will never see an on signal from the PCM and the pump will never run. These circuits pass between the PCM and the FPDM and will need verified.

The PCM and FPDM communicate via two wiresвЂ¦ The fuel pump COM circuit and the Fuel Pump Monitor circuit.

If the Driver module has no power supplied, it will never attempt to run the pump.

The ignition switch power is supplied to the FPDM to power the module and splices off to power the pump itself.

If the pump still refuses to run, there are a couple of other issues that can be present: If the pump runs, you have a circuit fault to the FRP or the sensor is shot. If unplugged (FRP) the fuel pump will be commanded on at a default value, you can check to see if the pump turns on and whether the vehicle runs.

The FRP sensor is on the fuel rail and can be unplugged electrically. In this case the PCM incorrectly believes that the fuel pressure is higher than required and shuts the fuel pump off. In rare cases, the FRP sensor will report erroneously excessive pressure. The PCM has a desired target fuel pressure based on the intake manifold pressure, the higher the manifold pressure, the harder the PCM will request the FPDM drive the fuel pump. (Yes the fuel pressure is variable depending engine operating conditions.) The pressure is determined by the PCM watching the input from the Fuel Rail Pressure (FRP) sensor. The FPDM supplies a variable ground signal to the fuel pump in order to control the pump speed and hence the fuel pressure. The fuel pump is ground side controlled by the Fuel Pump Driver Module (FPDM) When verifying the ground, verify the ground to the driver module as Tester indicated.

Ford focus fuel pump driver module problems