Circuit Description
The body control module (BCM) controls the courtesy lamps through the courtesy lamp low control circuit. The BCM grounds the courtesy lamp low control circuit which completes the interior lamps circuit, and the lamps illuminate.
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC B2654 Courtesy Lamp Low Control Circuit Low
Conditions for Running the DTC
The BCM must command the interior lamps output OFF.
Conditions for Setting the DTC
| • | The BCM detects an output that is low when a high is expected in the courtesy lamp low control circuit. |
| • | The condition above must be present for more than 0.3 seconds. |
Action Taken When the DTC Sets
The BCM stores DTC B2654 in memory.
Conditions for Clearing the DTC
| • | A current DTC B2654 clears if the short to ground or open in the courtesy lamp low control circuit is no longer detected by the BCM. |
| • | A history DTC B2654 clears after 100 consecutive error free ignition cycles with no BCM malfunction detected. |
Diagnostic Aids
| • | If the DTC B2654 is a history DTC, the fault 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 short to ground or open in the courtesy lamp low control circuit |
| - | Any courtesy lamp is intermittently shorted to ground or open internally. |
| - | The BCM is intermittently shorted to ground or open internally. |
Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: Interior Lights Dimming 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 to full bright then dim to OFF? | Go to Diagnostic Aids | Go to Step 3 |
3 |
Does the test lamp illuminate? | Go to Step 4 | Go to Step 10 |
4 |
Does the test lamp turn ON then turn OFF? | Go to Step 8 | Go to Step 5 |
5 | Does the test lamp remain illuminated with each command? | Go to Step 7 | Go to Step 6 |
6 | Test the courtesy lamp low control circuit for a short to battery positive voltage or an open. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 13 | Go to Step 9 |
7 | Test the courtesy lamp low control circuit for a short to ground. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 13 | Go to Step 9 |
8 | Inspect for poor connections at each of the interior lamps. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 13 | Go to Step 11 |
9 | Inspect for poor connections at the harness connector of the body control module (BCM). Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 13 | Go to Step 12 |
10 | Repair the high resistance or an open in the courtesy lamp supply voltage circuit. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 13 | -- |
11 | Replace the defective interior lamp. Refer to Instrument Panel Courtesy Lamp Bulb Replacement . Did you complete the replacement? | Go to Step 13 | -- |
12 | 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 13 | -- |
13 |
Does the DTC reset? | Go to Step 2 | System OK |
