Circuit Description
The body control module (BCM) controls the park lamp relay. The BCM grounds the park lamp relay coil control circuit which energizes the park lamp relay.
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC B2587 Park Lamp Control Circuit Low
Conditions for Running the DTC
The BCM must not be commanding the park lamp relay to energize.
Conditions for Setting the DTC
| • | The BCM detects a short to ground or open in the park lamp relay coil control circuit when the BCM is not trying to energize the park lamp relay. |
| • | The condition above must be present for more than 0.3 seconds. |
Action Taken When the DTC Sets
The BCM stores DTC B2587 in memory.
Conditions for Clearing the DTC
| • | A current DTC B2587 will clear if the BCM no longer detects a short to ground or open in the park lamp relay coil control circuit. |
| • | A history DTC B2587 will clear after 100 consecutive ignition cycles if the condition for the malfunction is no longer present. |
Diagnostic Aids
| • | If the DTC B2587 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 coil control circuit of the park lamp relay |
| - | The park lamp relay coil is intermittently shorted to ground or open internally. |
| - | The BCM is intermittently shorted to ground or open internally. |
Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: Exterior 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 |
Does the park lamp relay turn ON and OFF with each command? | 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 and OFF with each command? | 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 park lamp relay 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 park lamp relay 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 the park lamp relay. 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. 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 | Replace the RH IP Fuse block. Refer to Instrument Panel Electrical Center or Junction Block Replacement - Right Side in Wiring Systems. Did you complete the repair? | Go to Step 13 | -- |
11 | Replace the park lamp relay. Refer to Relay Replacement in Wiring Systems. Did you complete the replacement? | Go to Step 13 | -- |
12 | Replace the body control module. 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 |
