Diagnostic Aids
An intermittent may be caused by a poor connection, rubbed-through wire insulation or a broken wire inside insulation. Check PCM harness connector for backed out terminals. Connect a DVOM between affected terminal and ground. Wiggle related wires and connectors while watching DVOM for voltage reading change. Ensure coolant temperature sensor is not scaled improperly. See Code 15 in appropriate TESTS W/CODES article in this section. Ensure engine cooling system is operating normally.