Test C: Temperature Gauge Inaccurate
- Turn ignition switch to RUN position. If instrument cluster warning indicators and gauges are operating, go to next step. If instrument cluster warning indicators and gauges are not operating, perform TEST A: WARNING LIGHTS & GAUGES INOPERATIVE
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- Turn ignition switch to LOCK position. Disconnect engine coolant temperature sensor harness connector C1886. Turn ignition switch to RUN position. If temperature gauge indicates cold, go to next step. If temperature gauge does not indicate cold, go to step 4
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- Turn ignition switch to LOCK position. Using a jumper wire, ground White/Red wire terminal at temperature sensor harness connector C845. Turn ignition switch to RUN position. If temperature gauge does not indicate hot, go to next step. If temperature gauge indicates hot, replace temperature gauge sending unit.
- Turn ignition switch to LOCK position. Disconnect instrument cluster harness connector C808A. Measure resistance between ground and terminal No. 6 (White/Red wire) at instrument cluster harness connector C808A. See Figure
. If resistance is more than 10 k/ohms, go to next step. If resistance is 10 k/ohms or less, repair short to ground in White/Red wire.
- Measure resistance in White/Red wire between terminal No. 6 at instrument cluster harness connector C808A and temperature gauge sending unit harness connector C845. If resistance is 5 ohms or less, go to next step. If resistance is more than 5 ohms, repair open White/Red wire.
- Disconnect remaining instrument cluster harness connectors. Remove instrument cluster. Measure resistance between terminal No. 6 at instrument cluster harness connector C808A (component side) and temperature gauge terminal C1 on printed circuit. See Fig 1
. If resistance is 5 ohms or less, go to next step. If resistance is more than 5 ohms, replace printed circuit.
- Measure resistance between terminal No. 9 at instrument cluster harness connector C808A (component side) and temperature gauge terminal C3 on printed circuit. If resistance is 5 ohms or less, go to next step. If resistance is more than 5 ohms, replace printed circuit.
- Measure resistance between terminal No. 13 at instrument cluster harness connector C808A (component side) and temperature gauge terminal C2 on printed circuit. If resistance is 5 ohms or less, replace temperature gauge or instrument cluster as necessary. If resistance is more than 5 ohms, replace printed circuit.
Courtesy of FORD MOTOR CO.