Diagnostic Aids

Check for poor connection at PCM and Ion Sensing Module located on top of engine. Inspect harness connectors for backed-out terminals, improper mating, broken locks, improperly formed or damaged terminals and poor terminal connection. Inspect wiring harness for damage. If harness appears to be okay, use scan tool to observe KNOCK PRESENT, KNOCK SENSOR NOISE CHANNEL display while moving connectors and harnesses. A change in display will indicate location of fault. If DTC can not be duplicated, reviewing scan tool FAILURE RECORDS data can be useful in determining mileage and frequency of DTC occurrence.