P1237 - Fuel Pump Secondary Circuit
WARNING: This page does not describe the selected car, but rather 32 other vehicles, including the 2008 Mercury Sable, 2008 Mercury Mountaineer, 2008 Mercury Milan, 2008 Mercury Mariner, and 2008 Mercury Grand Marquis. However, it is still accessible from the selected car via links, so may be relevant.
P1237 - FUEL PUMP SECONDARY CIRCUIT
| Description: | This DTC indicates that the fuel pump driver module (FPDM) detected a fuel pump secondary circuit concern. The FPDM sends a message to the powertrain control module (PCM) through the fuel pump monitor (FPM) circuit indicating this concern was detected. The PCM sets the DTC when the message is received. | |||
| Possible Causes: |
|
|||
| Diagnostic Aids: | The FPDM sends a 75% duty cycle (750 ms on, 250 ms off) through the FPM circuit to the PCM while the concern is being detected by the FPDM. If the concern is no longer detected, the PCM returns to sending an all OK (50% duty cycle) message to the PCM. The FPDM controls pump speed by supplying a variable ground on the FP RTN circuit. | |||
| Application | Key On Engine Off | Key On Engine Running | Continuous Memory | |
| All | refer to PINPOINT TEST KB . | |||