Originally Posted by nilskje
B1681, I think indicates a PATS problem,the other:P1233 - Fuel System Disabled or Offline LS6/LS8:
For LS6/LS8, P1233 indicates the PCM is not receiving the fuel level information on SCP from the rear electronics module (REM). Refer to the Workshop Manual Section 413-01 for diagnostics.
The PCM monitors the fuel pump monitor (FPM) circuit from the fuel pump driver module (FPDM). With the key on, the FPDM continuously sends a duty cycle signal to the PCM through the FPM circuit. The test fails if the PCM stops receiving the duty cycle signal. Inertia fuel shutoff (IFS) switch needs to be reset
Open FPDM ground circuit
Open or shorted FPM circuit
Damaged IFS switch
Also for Escort/Tracer and Mustang:
Open FPDM PWR circuit
Open B+ circuit to constant control relay module (CCRM) pin 11
Open ground to CCRM pin 18 (Mustang)
Also for Continental:
Open VPWR circuit to FPDM
The PCM expects to see one of the following duty cycle signals from the FPDM on the FPM circuit: 1) 50% (500 msec on, 500 msec off), all OK. 2) 25% (250 msec on, 750 msec off), FPDM did not receive a fuel pump (FP) duty cycle command from the PCM, or the duty cycle that was received was invalid. 3) 75% (750 msec ON, 250 OFF), the FPDM has detected a fault in the circuits between the FPDM and the fuel pump
Ok...the pats code I believe was Me,I swapped out the ignition cylinder on Friday,had the dreaded key wont turn issue.
But...how do I reset the fuel pump switch when the Car is running????