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DTC B0688: Security Indicator Circuit Fault: Testing

WARNING: This page is about a different car, the 2002 GMC Savana, 2002 Chevrolet Chevy Express, 2001 GMC Savana, and 2001 Chevrolet Chevy Express. However, it is still accessible from the selected car via links, so may be relevant.
  1. If theft deterrent diagnostic system check has been performed, go to next step. If theft deterrent diagnostic system check has not been performed, go to THEFT DETERRENT DIAGNOSTIC SYSTEM CHECK  under SELF DIAGNOSTIC SYSTEM.
  2. Turn ignition switch to OFF position. Connect scan tool to Data Link Connector (DLC), located below steering column. See Figure . Turn ignition switch to RUN position. Using scan tool, command security indicator on and off. If security indicator does not change state, go to next step. If security indicator changes states with each command, go to DIAGNOSTIC AIDS  .
  3. Turn ignition switch to OFF position. Disconnect Passlock(tm) Module 16-pin harness connector. Turn ignition switch to RUN position. If security indicator is illuminated, go to next step. If security indicator is not illuminated go to step  5 .
  4. Check for short to ground in Yellow wire (security indicator control circuit) between Passlock(tm) module harness connector terminal B2 and Instrument Panel Cluster (IPC) harness connector terminal A4. See Fig 1 and Fig 2 . If Yellow wire is okay, go to step  6 . If Yellow wire is not okay, repair as necessary. After repair, go to step  9 .
    Fig 1: Identifying Passlock(tm) Module Harness Connector Terminals
    G00062259Courtesy of GENERAL MOTORS CORP.
    Fig 2: Identifying Instrument Panel Cluster Connector Terminals
    G00062262Courtesy of GENERAL MOTORS CORP.
  5. Check Passlock(tm) module connector for intermittent or poor terminal contact. If terminal contact is okay, go to step  8 . If terminal contact is not okay, repair as necessary. After repair go to step  9 .
  6. Check IPC connectors for intermittent or poor terminal contact. If terminal contact is okay, go to next step. If terminal contact is not okay, repair as necessary. After repair go to step  9 .
  7. Replace IPC. After repair go to step  9 .
  8. Replace Passlock(tm) module. After repair, go to next step.
  9. Using scan tool, clear DTCs. Operate vehicle to verify fault no longer exists. If DTC resets, go to step  2 .
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