When the headlamp switch is turned to the PARK or HEAD position, the body control module (BCM) applies battery positive voltage to the instrument panel (I/P) courtesy lamps. When a door is opened, the door latch assembly applies a ground to the BCM. The BCM supplies battery positive voltage to the courtesy lamp supply voltage circuit and applies a ground to the courtesy lamps low control circuit.
This diagnostic procedure supports the following DTC:
DTC B2558 Passenger Compartment Lamp Control Circuit High
At least one of the following conditions must exist:
• | At least one door is open. |
• | The interior lamps are commanded ON by the BCM. |
• | The interior lamps are commanded ON by the BCM. |
• | The interior lamp control circuit is shorted to battery positive voltage for 0.1 second. |
• | DTC B2558 is stored in the BCM memory. |
• | The BCM disables the interior lamp control output for the remainder of the ignition cycle. |
• | The conditions for setting the DTC are no longer present. |
• | A history DTC clears after 100 malfunction-free ignition cycles. |
• | The BCM receives the clear code command from the scan tool. |
• | If the DTC is a history DTC, the problem may be intermittent. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems. |
• | The following conditions may cause an intermittent malfunction to occur: |
- | An intermittent in the courtesy lamp low control circuit |
- | The BCM is intermittently shorted to battery positive voltage. |
Step | Action | Yes | No |
---|---|---|---|
Schematic Reference: Interior Lights Schematics Connector End View Reference: Master Electrical Component List in Wiring Systems | |||
1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information |
2 |
Do the courtesy lamps turn ON and OFF with each command? | Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems | Go to Step 3 |
3 |
Does the test light illuminate? | Go to Step 5 | Go to Step 4 |
4 | Inspect for poor connections at the harness connector 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 7 | Go to Step 6 |
5 | Repair the short to battery positive voltage in the courtesy lamp low control circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 7 | -- |
6 | Replace the BCM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming. Did you complete the replacement? | Go to Step 7 | -- |
7 |
Does the DTC reset? | Go to Step 2 | System OK |