Test E: Speedometer Or Odometer Inoperative Or Inaccurate

Drive vehicle at speeds more than 25 MPH and check operation of speedometer and odometer. If either speedometer or odometer do not operate normally, go to next step. If both speedometer and odometer operate normally, check system for intermittent failures. See appropriate BODY CONTROLS MODULE article.
Turn ignition switch to LOCK position. Remove instrument cluster. See INSTRUMENT CLUSTER under REMOVAL & INSTALLATION. Disconnect instrument cluster Gray 16-pin harness connector C1. Using DVOM, measure voltage (backprobe) between ground and instrument cluster harness connector C1 terminal No. 5 (White wire). See Figure . If battery voltage exists, go to next step. If battery voltage does not exist, repair open in White wire between instrument cluster and junction block. Junction block is located under left side of instrument panel.
Disconnect instrument cluster White 13-pin harness connector. Check for continuity in Black/Yellow wire between ground and instrument cluster White 13-pin harness connector terminal No. 2. See Figure . If continuity exists, go to next step. If continuity does not exist, repair open in Black/Yellow wire between instrument cluster White 13-pin harness connector terminal No. 2 and ground. Ground is located on right rear of engine compartment at intake manifold.
Check instrument cluster printed circuit for bad connections, cracks or other damage. If instrument cluster printed circuit is okay, go to next step. If instrument cluster is not okay, replace instrument cluster printed circuit.
Using DVOM, check continuity in Blue/Yellow wire between instrument cluster Gray 16-pin harness connector C1 terminal No. 9 and Vehicle Speed Sensor (VSS) harness connector terminal No. 1. VSS is located in left side of transmission in adapter case. If continuity does not exist, repair open in Blue/Yellow wire between instrument cluster and VSS. If continuity exists, replace speedometer.