B2471

DTC B2471 Interior Lamp Fault:

DTC B2471 Interior Lamp Fault (Part 1 Of 2):

DTC B2471 Interior Lamp Fault (Part 2 Of 2):

CIRCUIT DESCRIPTION
The BCM operates the interior lamps using the Delayed Interior Lamps (DIL) relay and the interior lamp relay. When the DIL relay is energized, it provides battery power to the coil of the interior lamp relay. Upon receiving various inputs, the BCM commands the interior lamps On by energizing the interior lamp relay at terminal C13. When the relay is energized, it provides a ground path for the interior lamps.

CONDITIONS FOR SETTING THE DTC
The BCM monitors the output to the interior lamps relay every second at terminal C13. The fault code is set only when the DIL relay is active, a DTC B1971 is not set and the feedback doesn't match the commanded state for 2 seconds (open circuit, short to B+ or ground).

ACTION TAKEN WHEN THE DTC SETS
^ The BCM continues to command the requested state until it is achieved or until it changes.
^ Stores a DTC B2471 in the BCM memory. The problem may intermittent if the DTC is a history DTC.

CONDITIONS FOR CLEARING THE DTC
^ The conditions for the fault are no longer present.
^ The use of a scan tool.
^ A history DTC will clear after 50 ignition cycles if the condition for the fault is no longer present.

DIAGNOSTIC AIDS
Try performing the tests shown while wiggle the wiring and the connectors. Wiggling the wires and the connectors can often cause the malfunction to appear. Refer to Intermittents and Poor Connections. Intermittents and Poor Connections

TEST DESCRIPTION
The following numbers refer to the step numbers on the diagnostic table:
2. When the interior lamp relay is commanded On/Off the status should match the commanded state. In most cases a no change in status indicates a circuit problem.
3. This test checks for proper voltage and ground input to the BCM. After checking the inputs, recheck for DTC B2471. If no external circuitry problems exist and B2471 continues to reset, a BCM internal failure is evident.
4. Commanding the delayed interior lamp (DIL) relay On with the scan tool, allows voltage to be supplied to the interior lamp relay coil. Because the BCM is not commanding the interior lamp relay On at this time, supplied voltage (B+) should be present at terminal C13, indicating that the circuit is complete.
12. The relay may be faulty if no circuit problems are verified. The multifunction relay contains the interior lamp relay and cannot be serviced separately.