Possible causes

– Faulty Fuel Pump Driver Module (FPDM)
– Fuel Pump Driver Module (FPDM) harness is open or shorted
– Fuel Pump Driver Module (FPDM) circuit poor electrical connection
– Faulty fuel pump

When is the code detected?

Fuel pump driver module has detected a fault in the fuel pump secondary circuit

Symptoms

– Engine Light ON (or Service Engine Soon Warning Light)
– Engine will not start

P1237 MERCURY Description

Fuel Pump Driver Modules (FPDM) controls the voltage to the Fuel Pump in order to maintain proper fuel pressure over the full operating range of the engine.

MERCURY Technical Service Bulletins for P1237 code