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DTC B2739: Key-In-Ignition Fault: Testing

  1. If BCM diagnostic system check was performed, go to next step. If BCM diagnostic system check was not performed, see procedures in BCM DIAGNOSTIC SYSTEM CHECK  .
  2. If BCM DTC B0608 is also set, see DTC B0608: BCM POWER MODING ERROR  . If BCM DTC B0608 is not set, go to next step.
  3. Turn ignition switch to LOCK position. Leave key fully inserted in ignition switch. Disconnect BCM Pink 32-pin connector C1. Using DVOM, check resistance between BCM harness connector C1, terminal D1 (Light Green wire) and ground. If resistance is less than 2 ohms, go to next step. If resistance is not less than 2 ohms, go to step 6).
  4. Leave DVOM connected as indicated in step 3). Remove key from ignition switch. If resistance is infinite, go to next step. If resistance is not infinite, go to step 8).
  5. Turn ignition switch to LOCK position. Reinstall all components and connectors. Turn ignition switch to RUN position. Using scan tool, clear DTCs. Turn ignition switch to LOCK, then RUN position. Check for DTCs. If DTC B2739 is set, go to step 13). If DTC B2739 is not set, go to step 14).
  6. Disconnect Black 48-pin connector C201 from instrument panel-to-steering column wiring harness, located behind instrument panel on right side of steering column. See Figure . Connect test light between battery voltage and connector C201 (male-side), terminal B4 (Black wire). If test light illuminates, go to next step. If test light does not illuminate, go to step 9).
  7. Using DVOM, check resistance between BCM harness connector C1, terminal D1 (Light Green wire) and connector C201, terminal B3 (Light Green wire). If resistance is less than 2 ohms, go to next step. If resistance is not less than 2 ohms, go to step 11).
  8. Leave DVOM connected as indicated in step 4). Disconnect Black 48-pin connector C201 from instrument panel-to-steering column wiring harness, located behind instrument panel on right side of steering column. If resistance is infinite, go to step 10). If resistance is not infinite, go to step 12).
  9. Repair poor connection or open in Black wire between connector C201 and ground. Go to step 15).
  10. Replace ignition key alarm switch. See INSTRUMENT PANEL article. Go to step 15).
  11. Repair poor connection or open in Light Green wire between BCM connector C1 and connector C201. Go to step 15).
  12. Repair short to ground in Light Green wire between BCM connector C1 and connector C201. Go to step 15).
  13. Replace BCM. See REMOVAL & INSTALLATION  . Reprogram BCM. See procedures in BCM PROGRAMMING  . Go to step 15).
  14. System is operating properly at this time. See DIAGNOSTIC AIDS. After any repairs are made, go to next step.
  15. Turn ignition switch to LOCK position. Reinstall all components and connectors. Turn ignition switch to RUN position. Using scan tool, clear DTCs. Check for DTCs. If any DTCs are current, perform BCM DIAGNOSTIC SYSTEM CHECK  . If no DTCs are current, system is operating properly.
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