Diagnostic Aids

WARNING: This page is about a different car, the 2002 Ford Pickup and 2002 Ford Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.

Enter this test only when all steps under QUICK TEST have been successfully completed and engine still does not start or if directed here from another test or chart. Powertrain Control Module (PCM) and Alternative Fuel Control Module (AFCM) transfer data through SCP network. DTCs U1260 (SCP (+) single ended circuit failure) and U1261 (SCP (-) single ended circuit failure) are set when AFCM does not receive or receives incorrect data from PCM. DTC U1262 (SCP communication bus fault) is set when Alternative Fuel Control Module (AFCM) has not received messages from Powertrain Control Module (PCM) for longer than 5 seconds. Possible causes for these faults are:

SCP (+) or SCP (-) communication link for open or short to ground.
Faulty compuvalve.
Faulty PCM.
SCP communication link.

NOTE: During bi-fuel diagnostics, intermittent failures are possible. Perform wiggle test and tap lightly on relays during testing. Ensure vehicle has LPG before continuing with diagnostics.