Intermittent Fault Diagnosis

Before proceeding with INTERMITTENT FAULT DIAGNOSIS, ensure that mechanical system tests and inspections do not reveal a problem. Check TSBs for possible repairs. Intermittent fault TEST PROCEDURES require duplicating circuit or component failure to identify problem. These TEST PROCEDURES may lead to computer module setting a DTC (on some systems) which may help in diagnosis.

If vehicle being tested does not produce DTCs, perform PARAMETER IDENTIFICATION (PID) DATA MONITOR PROCEDURE . Ensure all accessories as well as dome, trunk and hood lights are off. While monitoring PIDs, perform TEST PROCEDURES .