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DTC B2471: Interior Lights Fault: Testing

NOTE: If DTC B2471 is a history code, problem may be intermittent. Wiggle wires while performing the following test.
  1. If BCM system check was performed, go to next step. If BCM system check was not performed, go to BCM DIAGNOSTIC SYSTEM CHECK  under SYSTEM TESTS.
  2. Connect scan tool to DLC. 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. Problem is not present. Check for poor connection at BCM 32-pin, connector C2 terminal C13 (Brown/Purple wire). See Figure . Check all BCM power and ground circuits. See WIRING DIAGRAMS  . Ensure all connectors and components are connected. After repairs, go to step  12 .
  4. Select INTERIOR LIGHTS from light test menu in SPECIAL FUNCTIONS. Press OFF button on scan tool to command interior lights off. Using DVOM, backprobe and measure voltage between ground and BCM 32-pin, connector C2 terminal C13 (Brown/Purple wire). If battery voltage exists, go to next step. If battery voltage does not exist, go to step  6 .
  5. Disconnect multifunction relay module connector. See Figure . Select INTERIOR LIGHTS from light test menu in SPECIAL FUNCTIONS. Press ON button on scan tool to command interior lights on. Check voltage at multifunction relay module connector terminal No. 13 (Brown/Purple wire). See Figure . If less than 1 volt is indicated, go to step  11 . If more than 1 volt is indicated, go to step  10 .
  6. Disconnect BCM 32-pin connector C2. Using DVOM, check resistance between BCM connector C2 terminal C13 and multifunction relay module terminal No. 9 (Brown/Purple wire). If open circuit is found, go to step  8 . If circuit is okay, go to next step.
  7. Move DVOM lead from multifunction relay module terminal No. 9 (Brown/Purple wire) to ground. If resistance is infinite, go to step  13 . If resistance is not infinite, go to next step.
  8. Repair open in Brown/Purple wire between multifunction relay module and BCM. After repairs, go to step  12 .
  9. Repair short to ground in Brown/Purple wire between multifunction relay module and BCM. After repairs, go to step  12 .
  10. Repair short to voltage in Brown/Purple wire between multifunction relay module and BCM. After repairs, go to step  12 .
  11. Replace BCM. See BODY CONTROL MODULE (BCM)  under REMOVAL & INSTALLATION. Reprogram BCM. See PROGRAMMING  . Perform BCM DIAGNOSTIC SYSTEM CHECK  under SYSTEM TESTS.
  12. Use scan tool to clear DTCs. Recheck for DTCs. If DTC B2471 is present, go to step  2 . If DTC B2471 is not present, system is okay.
  13. Replace multifunction relay module. Reinstall all connectors and components. Using scan tool, clear DTCs. Check for DTCs. If DTC B2471 is set, go to step  12 . If DTC B2471 is not set, go to BCM DIAGNOSTIC SYSTEM CHECK  under SYSTEM TESTS.
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