Coolant Temperature Gauge Circuit Test: Q45

Test coolant temperature sending unit. See COOLANT TEMPERATURE SENDING UNIT under COMPONENT TESTS. If coolant temperature sending unit is okay, go to next step. If coolant temperature sending unit is defective, replace coolant temperature sending unit.
Partially remove instrument cluster, leaving harness connectors connected. Turn ignition switch to RUN position. Ground screw "C" on back of instrument cluster for less than 10 seconds and observe temperature gauge operation. See Figure . If temperature gauge moves to full, go to next step. If temperature gauge does not move to full, replace printed circuit or temperature gauge as necessary.
Disconnect instrument cluster White 16-pin harness connector N14. See Figure . Ensure coolant temperature sending unit harness connector is still disconnected. Measure resistance in Blue/Black wire between terminal No. 46 at instrument cluster harness connector N14 and coolant temperature sensor harness connector. See Figure . If resistance is 5 ohms or less, go to next step. If resistance is greater than 5 ohms, repair open in Blue/Black wire.
Check continuity between ground and terminal No. 46 (Blue/Black wire) at instrument cluster harness connector N14. If continuity exists, repair short to ground in Blue/Black wire. If continuity does not exist, coolant temperature gauge circuit is okay at this time.