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DTC B2471: Interior Lights Fault: Testing

  1. If BCM system check was performed, go to next step. If BCM system check was not performed, go to BCM SYSTEM CHECK  .
  2. Connect scan tool. Select INTERIOR LIGHTS from light test menu in SPECIAL FUNCTIONS. While observing scan tool, press on and off buttons on scan tool several times. If status changes and interior lights operate with commanded state, go to next step. If status does not change or interior lights do not operate with commanded state, go to step 4).
  3. Check for poor connection at BCM 32-pin, connector C2, terminal C13 (Brown/Purple wire). Check all BCM power and ground circuits. See WIRING DIAGRAMS  . Ensure all connectors and components are connected. Using scan tool, clear codes. Check for codes. If DTC B2471 is set, go to step 14). If DTC B2471 is not set, see procedures in BCM SYSTEM CHECK  .
  4. Select DELAY INTERIOR LIGHTS from light test menu in SPECIAL FUNCTIONS. Press on button on scan tool to command delay interior lights on. Check voltage at BCM 32-pin, connector C2, terminal C13 (Brown/Purple wire). If battery voltage exists, go to step 3). If battery voltage does not exist, go to next step.
  5. Disconnect multifunction relay module connector. See Figure . Check voltage at multifunction relay module connector terminal No. 5 (Red wire). If battery voltage exists, go to next step. If battery voltage does not exist, go to step 7).
  6. Disconnect BCM 32-pin C2 connector. Using DVOM, check resistance between BCM connector C2, terminal C13 (Brown/Purple wire) and multifunction relay module terminal No. 9 (Brown/Purple wire). If resistance is less than 2 ohms, go to step 8). If resistance is not less than 2 ohms, go to step 9).
  7. Repair open in Red wire between multifunction relay module and instrument panel fuse block.
  8. Move DVOM lead from multifunction relay module terminal No. 9 (Brown/Purple wire) to ground. If resistance is infinite, go to step 10). If resistance is not infinite, go to step 11).
  9. Repair open in Brown/Purple wire between multifunction relay module and BCM. Perform BCM SYSTEM CHECK  .
  10. Leaving DVOM connected as specified in step 8), switch DVOM to DC volts scale. Record voltage reading. Turn ignition switch to ON position. Record voltage reading. If both voltage readings are less than one volt, go to step 12). If both voltage readings are not less than one volt, go to step 13).
  11. Repair short to ground in Brown/Purple wire between multifunction relay module and BCM. Perform BCM SYSTEM CHECK  .
  12. Replace multifunction relay module. Reinstall all connectors and components. Using scan tool, clear codes. Check for codes. If DTC B2471 is set, go to step 14). If DTC B2471 is not set, go to BCM SYSTEM CHECK  .
  13. Repair short to battery in Brown/Purple wire between multifunction relay module and BCM. Perform BCM SYSTEM CHECK  .
  14. Replace BCM. See BODY CONTROL MODULE (BCM)  under REMOVAL & INSTALLATION. Reprogram BCM. See PROGRAMMING  . Perform BCM SYSTEM CHECK.
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