LEMON Manuals: Even more car manuals for everyone
Home >> GMC >> 2001 >> Jimmy 2D Utility, 4WD, Standard >> Repair and Diagnosis >> Accessories & Equipment >> Gauges & Instrument Panels >> Analog Instrument Panels >> Diagnostic Tests >> DTC P0608: Vehicle Speed Out Of Range >> Diagnostic Procedure

Diagnostic Procedure

  1. If Instrument Panel Cluster (IPC) diagnostic system check has been performed, go to next step. If IPC diagnostic system check has not been performed, see INSTRUMENT PANEL CLUSTER DIAGNOSTIC SYSTEM CHECK  under SELF-DIAGNOSTIC SYSTEM.
  2. Turn ignition switch to OFF position. Connect scan tool to Data Link Connector (DLC). Raise and support vehicle such that drive wheels are off ground. Start engine. On A/T vehicles, place transmission selector lever into DRIVE. On M/T vehicles, shift transmission into 3rd gear. On all models, observe VEHICLE SPEED SENSOR (VSS) parameter in PCM data list. If VSS parameter matches speedometer indication, system is functioning properly at this time. Check wiring and connectors for intermittent fault. See WIRING DIAGRAMS  . If parameter does not match speedometer indication, go to next step.
  3. Turn ignition switch to OFF position. Disconnect PCM connector C2. Connect Signal Generator and Instrument Panel Tester (J33431-C) to PCM connector C2 terminal No. 17 (2.2L engines) or PCM connector C2 terminal No. 50 (4.3L engines) and vehicle ground. See Figure . Turn ignition switch to ON position. Using signal generator, set vehicle speed at 55 MPH. If speedometer indicates approximately 55 MPH, go to step  5 . If speedometer does not indicate approximately 55 MPH, go to next step.
  4. Check VSS circuit between IPC and PCM. On 2.2L engines, check Dark Green wire between PCM connector C2 terminal No. 17 and IPC connector A4. See Figure . See WIRING DIAGRAMS  . On 4.3L engines, check Dark Green/White wire between PCM connector C2 terminal No. 50 and connector C203 terminal E11. See Fig 1 . Check Dark Green wire between connector C203 and IPC connector terminal A4. See Figure . See WIRING DIAGRAMS  . On all models, check circuit for open or short to ground. Repair wiring as necessary, then go to step  9 . If no problem is found, go to step  6 .
  5. Check PCM connector for poor connections or corroded terminals. Repair connection as necessary, then go to step  9 . If no problem is found, go to step  7 .
  6. Check IPC connector for poor connections or corroded terminals. Repair connection as necessary, then go to step  9 . If no problem is found, go to step  8 .
  7. Replace PCM. See REMOVAL, OVERHAUL & INSTALLATION - TRUCKS article in ENGINE PERFORMANCE. When repair is complete, go to step  9 .
  8. Replace IPC. See INSTRUMENT PANEL CLUSTER  under REMOVAL & INSTALLATION. When repair is complete, go to next step.
  9. Using scan tool, clear DTCs. Operate vehicle at engine speed greater than 400 RPM and electrical system between 6 and 14 volts. Monitor for PCM DTCs. If P0608 resets, go to step  2 . If DTC does not reset, repair is complete.
Fig 1: Identifying Connector C203 Terminals
G00061861Courtesy of GENERAL MOTORS CORP.
scientia non olet · About LEMON Manuals