Test G: Speedometer Reads Zero Or Indication Varies Erratically
- Turn ignition off. Remove instrument cluster. See INSTRUMENT CLUSTER
under REMOVAL & INSTALLATION. Leave connectors connected. Set voltmeter on AC scale. Connect voltmeter between instrument cluster connector C274 terminal No. 4 (Black/Red wire) and C272 terminal No. 3 (Pink/Blue wire). See Figure
and Figure
. Drive vehicle at indicated speeds while observing voltmeter. See SPEEDOMETER VOLTAGE
table. If voltage readings are as specified, replace instrument cluster. See INSTRUMENT CLUSTER
under REMOVAL & INSTALLATION. If voltage readings are not as specified, go to next step.
SPEEDOMETER VOLTAGE
| Indicated MPH |
Volts AC |
| 5 |
0.5 |
| 10 |
1.0 |
| 15 |
1.6 |
| 20 |
2.0 |
| 25 |
2.4 |
| 30 |
2.8 |
| 35 |
3.1 |
| 40 |
3.4 |
| 45 |
3.6 |
| 650 |
3.9 |
| 655 |
4.2 |
| 60 |
4.4 |
- Turn ignition off. Disconnect Vehicle Speed Sensor (VSS) wiring harness connector. Disconnect instrument cluster connectors C274 and C272. Measure resistance of the Pink/Blue wire between instrument cluster connector C272 terminal No. 3 and VSS wire connector. Measure resistance of Black/Red wire between instrument cluster connector C274 terminal No. 4 and VSS wire harness connector. Resistance should be less than 5 ohms. Measure resistance between ground and instrument cluster connector C272 terminal No. 3 (Pink/Black wire). Resistance should be more than 10,000 ohms. If resistances are as specified, replace VSS. If resistances are not as specified, repair faulty circuit.