Circuit Description
The Body Control Module (BCM) receives an active ground. The sole purpose of this input is to provide a ground for all courtesy lamp current flowing through the theater dim output.
Conditions for Running the DTC
If the input does not match a normal ground potential.
Conditions for Setting the DTC
| • | The BCM detects a open when a ground is expected. |
| • | The condition above must be present for more then .3 seconds |
Action Taken When the DTC Sets
The BCM stores DTC B2559 in memory.
Conditions for Clearing the DTC
| • | A current DTC B2559 will clear if the open is no longer detected by the BCM |
| • | A history DTC B2559 will clear after 100 consecutive ignition cycles if the condition for the malfunction is no longer present nor any other malfunction in the BCM is detected. |
Diagnostic Aids
| • | If the DTC B2559 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 open in the theater dimming ground circuit. |
| - | The BCM is intermittently opened. |
Test Description
The number(s) below refer to the step number(s) on the diagnostic table.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 | Did you perform the Lighting Diagnostic System Check? | -- | Go to Step 2 | |
2 |
Do the I/P lamps turn to full bright then dim to off? | -- | Go to Diagnostic Aids | Go to Step 3 |
Test the theater dimming ground signal circuit of the BCM for a open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 6 | Go to Step 4 | |
4 | Inspect for poor connections at the harness connector of the body control module]. 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 6 | Go to Step 5 |
5 |
Important: Perform the set up procedure for the body control module. Replace the BCM. Refer to Body Control Module Replacement . Did you complete the replacement? | -- | Go to Step 6 | -- |
6 |
Does the DTC reset? | -- | Go to Step 2 | System OK |
