Circuit Description
The body control module (BCM) supplies battery positive voltage to the reading lamps and both visor vanity mirror lamps. In the event that any of these lamps were to remain illuminated for more than 20 minutes with the ignition switch in the OFF position, the BCM will deactivate the inadvertent power courtesy lamps supply voltage circuit to prevent a total battery discharge condition.
Conditions for Running the DTC
The battery voltage must be between 9.0-16.0 volts.
Conditions for Setting the DTC
| • | The inadvertent power courtesy lamps supply voltage circuit to the reading lamps and both visor vanity mirror lamps is shorted to ground for more than 1 second. |
| • | There is a loss of the rear fuse block TBC 4 battery supply voltage to the BCM for more than 1 second while one or more of the lamps in the inadvertent power circuit have been activated. |
Action Taken When the DTC Sets
The reading lamps and both visor vanity mirror lamps will not operate.
Conditions for Clearing the MIL/DTC
| • | This DTC will clear on current status after the condition for setting the fault is corrected. |
| • | A history DTC will clear after 100 consecutive ignition cycles without a fault present. |
| • | History and current DTC(s) can be cleared using a scan tool. |
Diagnostic Aids
Perform a visual inspection for loose or poor connections at all related components. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.
Test Description
The numbers below refer to the step numbers on the diagnostic table.
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This step test determines if an open or short to ground exists.
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This step test determines if a short to ground exists in the lamp wiring or internally within the BCM.
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This step test determines if an open exists in the body wiring harness extension harness or internally within the BCM.
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After replacement of the BCM you must calibrate the new module for proper operation.
Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: Interior Lights Schematics Connector End View Reference: Lighting Systems Connector End Views or Body Control System Connector End Views in Body Control System | |||
1 | Did you perform the Lighting System Diagnostic System Check? | Go to Step 2 | |
Inspect the TBC 4 fuse in the rear fuse block. Is the fuse good? | Go to Step 4 | Go to Step 3 | |
Test the inadvertent power courtesy lamps supply voltage circuit for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 9 | Go to Step 5 | |
Test the TBC 4 battery positive supply voltage circuit at the body wiring harness extension harness connector at the body control module (BCM) for battery voltage. Refer to Circuit Testing in Wiring Systems. Is battery voltage present? | Go to Step 5 | Go to Step 6 | |
5 | Inspect for poor connections at the harness connectors of the BCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 9 | Go to Step 8 |
6 | Inspect for poor connections at the body wiring harness extension harness connectors. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 9 | Go to Step 7 |
7 | Replace the body wiring harness extension harness to the BCM. Refer to Body Control Module Body Wiring Harness Extension Harness Replacement in Body Control System. Did you complete the replacement? | Go to Step 9 | -- |
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Important: Perform the setup procedure for the BCM. Replace the BCM. Refer to Body Control Module Replacement in Body Control System. Did you complete the replacement? | Go to Step 9 | -- | |
9 |
Does the DTC reset? | Go to Step 2 | System OK |
