Circuit Description
The PZM may command the interior lamps through a discrete output to the courtesy lamps relay. The energized relay provides a ground for the interior lamps.
The PZM will test for a short to ground when Inadvertent power is active and the Interior lamps output is inactive and DTC B1971 is not current.
Conditions for Setting the DTC
The commanded state of the interior lamps does not match the feedback state.
Action Taken When the DTC Sets
The PZM continues to command the requested state until the instrument cluster revokes the request.
Conditions for Clearing the DTC
The commanded state matches the feedback state.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 | Did you perform the Lighting System Diagnostic System Check? | -- | Go to Step 2 | |
2 |
Is battery voltage measured? | -- | Go to Step 3 | Go to Step 7 |
3 | Measure voltage from the courtesy relay terminal A9 (ORN) to terminal B7 (DK BLU) Is battery voltage measured? | -- | Go to Step 4 | Go to Step 5 |
4 | Replace the courtesy relay. Is the repair complete? | -- | Go to Step 9 | -- |
5 | Inspect CKT 1393 (DK BLU) for an open. Refer to Testing for Continuity in Wiring Systems. Is CKT 1393 OK? | -- | Go to Step 6 | Go to Step 8 |
6 | Replace the PZM. Refer to Body Control Module Replacement in Body Control Systems. Is the repair complete? | -- | Go to Step 9 | -- |
7 | Repair the open or short to ground in CKT 640 (ORN). Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Step 9 | -- |
8 | Repair the suspect wiring. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Step 9 | -- |
9 |
Does the DTC reset? | -- | Go to Step 2 | System OK. |
