Fuel Pump Control Module
The FP signal is a duty cycle command sent from the PCM to the fuel pump control module. The fuel pump control module uses the FP command to operate the fuel pump at the speed requested by the PCM or to turn the fuel pump off. A valid duty cycle to command the fuel pump on, is in the range of 15-47%. The fuel pump control module doubles the received duty cycle and provides this voltage to the fuel pump as a percent of the battery voltage. When the ignition is turned on, the fuel pump runs for about 1 second and is requested off by the PCM if engine rotation is not detected.
FUEL PUMP DUTY CYCLE OUTPUT FROM PCM
| FP Duty Cycle Command | PCM Status | Fuel Pump Control Module Actions |
| 0-15% | Invalid off duty cycle | The fuel pump control module sends a 20% duty cycle signal on the fuel pump monitor (FPM) circuit. The fuel pump is off. |
| 37% | Normal low speed operation. | The fuel pump control module operates the fuel pump at the speed requested. The fuel pump control module sends a 60% duty cycle signal on FPM circuit. |
| 47% | Normal high speed operation. | The fuel pump control module operates the fuel pump at the speed requested. The fuel pump control module sends a 60% duty cycle signal on FPM circuit. |
| 51-67% | Invalid on duty cycle. | The fuel pump control module sends a 20% duty cycle signal on the FPM circuit. The fuel pump is off. |
| 67-83% | Valid off duty cycle | The fuel pump control module sends a 60% duty cycle signal on FPM circuit. The fuel pump is off. |
| 83-100% | Invalid on duty cycle. | The fuel pump control module sends a 20% duty cycle signal on the FPM circuit. The fuel pump is off. |
The fuel pump control module communicates diagnostic information to the PCM through the FPM circuit. This information is sent by the fuel pump control module as a duty cycle signal. The 5 duty cycle signals that may be sent are listed in the following table. Some vehicles, e.g. the 5.2L Mustang, use two fuel pump control modules to supply enough fuel to the engine. The fuel pump modules are the same, there are simply two of them ("A" and "B"). The second pump uses a different set of DTCs for the same set of faults. Both pumps are driven by the same PCM output.
FUEL PUMP CONTROL MODULE DUTY CYCLE SIGNALS
| Duty Cycle | Comments |
| 20% | This duty cycle indicates the fuel pump control module is receiving an invalid duty cycle from the PCM. |
| 30% | This duty cycle indicates a pump driver module (PEM) internal error. This status in applicable only to Omron Gen.II or higher modules. |
| 40% | For vehicles with event notification signal, this duty cycle indicates the fuel pump control module is receiving an invalid event notification signal from the RCM. For vehicles without event notification signal, this duty cycle indicates the fuel pump control module is functioning normally. |
| 60% | For vehicles with event notification signal, this duty cycle indicates the fuel pump control module is functioning normally. |
| 80% | This duty cycle indicates the fuel pump control module is detecting a concern with the secondary circuits. |
| DTCs | P025A - Fuel Pump A Control Circuit (open/shorts) P025B - Invalid Fuel Pump A Control Data (20% duty cycle from FPM) P0627 - Fuel Pump A Secondary Circuit (80% duty cycle from PFM) P064A - Fuel Pump A Driver Module Internal Error (30% duty cycle from PFM) U2010B - Fuel Pump A Disabled Circuit (40% duty cycle from FPM) U0109 - Loss of Communication with Fuel Pump Module A |
| Monitor Execution | Once per driving cycle |
| Monitor Sequence | None |
| Sensors OK | |
| Monitoring Duration | 2 seconds |
| Entry Condition | Minimum | Maximum |
| Battery Voltage | 11 volts |
| P025A
- Smart Fuel Pump output driver in PCM/ECM indicates fault P025B - Fuel Pump Monitor duty cycle feedback of 20% P0627 - Fuel Pump Monitor duty cycle feedback of 80% P064A - Fuel Pump Monitor duty cycle feedback of 30% U210B - Fuel Pump Monitor duty cycle feedback of 40% U0191 - No Fuel Pump Monitor duty cycle feedback (i.e. 0% or 100% duty cycle) |
| DTCs | P025A - Fuel Pump A/B Control Circuit (opens/shorts) P027B - Invalid Fuel Pump B Control Data (20% duty cycle from FPM) P2632 - Fuel Pump B Secondary Circuit (80% duty cycle from PFM) P26EA - Fuel Pump B Driver Module Internal Error (30% duty cycle from PFM) U2010C - Fuel Pump B Disabled Circuit (40% duty cycle from FPM) U016C - Loss of Communication with Fuel Pump Module B |
| Monitor Execution | once per driving cycle |
| Monitor Sequence | None |
| Sensors OK | |
| Monitoring Duration | 2 seconds |
| Entry Condition | Minimum | Maximum |
| Battery Voltage | 11 volts |
| P025A
- Smart Fuel Pump output driver in PCM/ECM indicates fault P027B - Fuel Pump Monitor duty cycle feedback of 20% P2632 - Fuel Pump Monitor duty cycle feedback of 80% P26EA - Fuel Pump Monitor duty cycle feedback of 30% U210C - Fuel Pump Monitor duty cycle feedback of 40% U016C - No Fuel Pump Monitor duty cycle feedback (i.e. 0% or 100% duty cycle) |