Speedometer Malfunction
NOTE:
Perform INSTRUMENT CLUSTER TEST 1A before proceeding with this test. For connector terminal identification and wiring diagrams, see
BODY CONTROL COMPUTER - INTRODUCTION. Perform VERIFICATION TEST: VER-2A after each repair.
CAUTION:
Always turn ignition switch to OFF position prior to disconnecting or connecting any module connector.
- Using scan tool, select BODY SYSTEMS TESTS, then PCM MONITOR. If scan tool does not display ACTIVE ON THE BUS, go to TEST 8A in appropriate VEHICLE COMMUNICATIONS article. If scan tool displays ACTIVE ON THE BUS, go to next step.
- Raise and support vehicle. Start engine. Ensure traction control system is off (if equipped). Place shift lever in Drive. Using scan tool, select MIC MONITORS. Read Vehicle Speed Signal (VSS). If vehicle speed increases proportionally as accelerator is depressed, replace instrument cluster. If vehicle speed does not increase, go to appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE.