Circuit Description
The PZM commands the daytime running lamps (DRL) ON or OFF through a discrete output to the DRL relay. The DRL is only active under the following conditions:
| • | The ignition is in the RUN or START position. |
| • | The twilight sentinel is not active. |
| • | The headlamps (low beam or high beam) and front foglamps are OFF. |
| • | The transmission is not in PARK. |
When the relay is energized, the relay places the high beams in a series circuit, providing lower illumination for the DRL.
Conditions for Setting the DTC
A short to ground is tested under the following conditions:
| • | Ignition 1 is ON. |
| • | The DRL is inactive. |
| • | The instrument cluster verifies that the vehicle has DRL. |
A short to battery will be tested under the following conditions:
| • | Ignition 1 is OFF or both ignition 1 DRLs are active. |
| • | The instrument cluster verifies that the vehicle has DRL. |
Action Taken When the DTC Sets
The PZM continues to command the state requested until the state is achieved or changes.
Conditions for Clearing the DTC
The commanded state matches the feedback state for 2 consecutive monitoring cycles.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 | Was the Body Control Module System Diagnostic Check performed? | -- | Go to Step 2 | |
2 |
Is the voltage within the specified range? | 10-15 V | Go to Step 3 | Go to Step 5 |
3 |
Do the DRLs turn on? | -- | Go to Step 4 | Go to Step 6 |
4 | Replace the PZM. Refer to Body Control Module Replacement . Is the repair complete? | -- | -- | |
5 | Repair the open or the short to ground in CKT 439 (PNK). Is the repair complete? | -- | -- | |
6 | Inspect CKT 592 (LT GRN/BLK) for an open, a short to ground, or a short to power. Was an open or a short found? | -- | Go to Step 8 | Go to Step 7 |
7 | Replace the DRL relay. Is the repair complete? | -- | -- | |
8 | Repair the open CKT 592 (LT GRN/BLK). Is the repair complete? | -- | -- |
