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Malfunction Indicator Light Inoperative

  1. If powertrain diagnostic system check was performed, go to next step. If powertrain diagnostic system check was not performed, go to POWERTRAIN DIAGNOSTIC SYSTEM CHECK  under DIAGNOSTIC SYSTEM CHECKS.
  2. Check GAUGES fuse No. 9 (10-amp) located in instrument panel fuse block. If fuse is okay, go to next step. If fuse is blown, go to step  10.
  3. Turn ignition off. Disconnect Powertrain Control Module (PCM) connectors. PCM is located on right rear of engine compartment. Turn ignition on. Connect a 3-amp fused jumper between ground and PCM connector C2 terminal No. 46 (Brown/White wire). See Fig 1. Observe Malfunction Indicator Light (MIL). If MIL does not illuminate, go to next step. If MIL illuminates, go to step  9.
  4. If fused jumper wire blows, go to step  11. If fused jumper wire does not blow, go to next step.
  5. Turn ignition off. Remove the Instrument Panel Cluster (IPC). See REMOVAL & INSTALLATION in appropriate ANALOG INSTRUMENT PANELS article in ACCESSORIES & EQUIPMENT. Using DVOM, measure resistance of Brown/White wire between IPC connector terminal A8 and PCM connector C2 terminal No. 46. See Fig 2. If resistance is 5 ohms or less, go to next step. If resistance is more than 5 ohms, repair open in Brown/White wire. After repairs, go to step  14.
  6. Using a test light connected to ground, probe IPC connector terminal A3 (Pink wire). Turn ignition on. If test light does not illuminate, go to next step. If test light illuminates, go to step  8.
  7. Repair open in Pink wire between GAUGES fuse in instrument panel fuse block and IPC. After repairs, go to step  14.
  8. Check for faulty connections at IPC connector. If faulty connections are found, repair as necessary. After repairs, go to step  14. If connections are okay, go to step  12.
  9. Check for faulty connections at PCM connector. If faulty connections are found, repair as necessary. After repairs, go to step  14. If connections are okay, go to step  13.
  10. Repair the short to ground in Pink wire between GAUGES fuse in instrument panel fuse block and IPC. Replace GAUGES fuse. After repairs, go to step  14.
  11. Repair the short to voltage in Brown/White wire between IPC connector terminal A8 and PCM connector C2 terminal No. 46. After repairs, go to step  14.
  12. Replace IPC. After repairs, go to step  14.
  13. Replace PCM. See REMOVAL, OVERHAUL & INSTALLATION - CARS article. After repairs, go to next step.
  14. Recheck operation on MIL. If MIL operates properly, repair is complete. If MIL does not operate properly, go to step  2.
Fig 1: Identifying Powertrain Control Module Connectors & Terminals
G00035735Courtesy of GENERAL MOTORS CORP.
Fig 2: Identifying Instrument Cluster Connector Terminals
G93C41402Courtesy of GENERAL MOTORS CORP.