Diagnostic Aids

Check for shifted/skewed sensor, loose or intermittent connections in ECT circuit, corroded connectors or resistance in circuit, faulty thermostat, cooling fan malfunction or extreme ambient temperature.

An intermittent malfunction may be caused by a poor connection, rubbed-through wire insulation, or a wire broken inside insulation. Inspect harness connectors for backed-out terminals, improper mating, broken locks, improperly formed or damaged terminals, or poor terminal-to-wire connections before component replacement.