Test F: Speedometer/Odometer Inaccurate

Remove instrument panel. See INSTRUMENT CLUSTER under REMOVAL & INSTALLATION. With ignition switch in OFF position, connect a voltmeter between "S" terminal and "G" terminal on speedometer (back of instrument cluster). Place voltmeter in AC volts position.
NOTE: Instrument cluster connector C268 must remain connected.

Drive vehicle and note speed to voltage readings. Compare noted readings to SPEED-TO-VOLTAGE COMPARISON table. If voltage readings are correct, replace speedometer. If readings are not correct, go to next step.

SPEED-TO-VOLTAGE COMPARISON

Speed - MPH (KM/H)	Approximate Voltage
0 (0)	0
5 (8)	0.5
10 (16)	1.0
15 (24)	1.6
20 (32)	2.0
25 (40)	2.4
30 (48)	2.8
35 (56)	3.1
40 (64)	3.4
45 (72)	3.6
50 (80)	3.9
55 (88)	4.2
60 (96)	4.4

With ignition switch in OFF position, ensure the 4 screws holding speedometer to instrument cluster printed circuit are securely fastened. Measure resistance between speedometer "S" terminal and instrument cluster connector C268 terminal No. 3 (Pink/Blue wire), speedometer "G" terminal and instrument cluster connector C268 terminal No. 5 (Black/Red wire), and speedometer "B" terminal and instrument cluster connector C268 terminal No. 2 (Blue wire). See Figure - Figure . If resistances are less than 5 ohms, go to next step. If resistances are more than 5 ohms, replace instrument cluster printed circuit. See PRINTED CIRCUIT under REMOVAL & INSTALLATION.
With ignition switch in OFF position and instrument cluster still removed, disconnect instrument cluster connector C268 and Vehicle Speed Sensor (VSS) connector. Measure resistance of Pink/Blue wire between VSS connector and instrument cluster connector C268 terminal No. 3. Measure resistance between ground and instrument cluster connector C268 terminal No. 3 (Pink/Blue wire). Measure resistance of Black/Red wire between VSS connector and instrument cluster connector C268 terminal No. 5. If resistances are less than 5 ohms between instrument cluster and VSS, and more than 10 k/ohms between Pink/Blue wire at instrument cluster and ground, replace VSS. If resistances are more than 5 ohms between instrument cluster and VSS, and less than 10 k/ohms between Pink/Blue wire at instrument cluster and ground, service wire(s) in question.