Fuel Pump (FP)
The fuel pump (FP) signal is a duty cycle command sent from the PCM to the fuel pump driver module (FPDM). The FPDM uses the FP command to operate the fuel pump at the speed requested by the PCM or to turn the pump off.
FUEL PUMP DUTY CYCLE OUTPUT FROM PCM
| FP Duty Cycle Command | PCM Status | FPDM Actions |
|---|---|---|
| 0-5% | PCM will not output this duty cycle. | Invalid FP duty cycle. FPDM sends 25% duty cycle signal on the fuel pump monitor (FPM) circuit. The fuel pump is off. |
| 5-51% | Normal operation. | FPDM operates the fuel pump at the speed requested. FP duty cycle x 2 = pump speed % of full on. (for example FP duty cycle equals 42%. 42 x 2 equals 84. Pump is run at 84% of full on). FPDM sends 50% duty cycle signal on FPM circuit. |
| 51-67.5% | PCM will not output this duty cycle. | Invalid FP duty cycle. FPDM sends 25% duty cycle signal on the fuel pump monitor (FPM) circuit. The fuel pump is off. |
| 67.5-82.5% | To request the fuel pump off, the PCM outputs a 75% duty cycle. | Valid fuel pump off command from PCM. FPDM does not operate the fuel pump. FPDM sends a 50% duty cycle signal on the FPM circuit. |
| 82.5-100% | PCM will not output this duty cycle. | Invalid FP duty cycle. FPDM sends 25% duty cycle signal on the FPM circuit. The fuel pump is off. |
NOTE:
Also refer to FUEL PUMP MONITOR (FPM) and FUEL PUMP DRIVER MODULE (FPDM) .