Step
| Action
| Value(s)
| Yes
| No
|
1
|
- Turn the ignition OFF.
- Ensure the ambient light sensor does not have any obstruction
.
- Connect a scan tool.
- Turn the ignition to the ON position.
- Using the scan tool, check for any DTCs in the body control module
(BCM).
Does the scan tool show any DTCs?
| --
| Go to
Diagnostic System Check - Body Control System
in Body Control System
|
Go to Step 2
|
2
| Using the
scan tool, read the head lamp relay feedback status in the BCM.
Does the scan tool show the status of ON?
| --
|
Go to Step 3
|
Go to Step
4
|
3
|
- Ensure the headlamp switch is in the auto position.
- Turn the ignition OFF.
- Disconnect the BCM.
- Using J35616A tool, connect a test lamp from terminal A11 of
C2 at BCM.
Does the test lamp light?
| --
|
Go to Step
5
|
Go to Step
4
|
4
|
- Reconnect the BCM if you disconnected the BCM in a previous step.
- Turn the ignition ON, engine OFF.
- Using the scan tool, read the ambient light sensor voltage in
the the BCM.
- While monitoring the scan tool, cover the ambient light sensor,
then induce a light source to the sensor.
Does the sensor voltage vary within the specified ranges?
| 4.7- 2.2V (DRL
on), 0.2- 1.3V (Headlamps on)
|
Go to Step
6
| Go to
Diagnostic System Check - Body Control System
in Body Control System
|
5
| Locate and
repair CKT 352 (WHT) for a short to voltage between the underhood bussed electrical
center (UBEC) and the BCM.
Is the repair complete?
| --
| System OK
| --
|
6
|
- Ensure the headlamp switch is in the auto position.
- Using the scan tool, command the headlamps OFF.
Do the headlamps go OFF?
| --
| System OK
|
Go to Step
7
|
7
| Replace the BCM. Refer to
Body Control Module Replacement
in Body Control System.
Is the repair complete?
| --
| System OK
| --
|
