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
| Turn the
headlamps to the ON position.
Do the headlamps come on?
| --
|
Go to Step
3
| Go to
Low and High Beams Headlamps Inoperative
.
|
3
| 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 5
|
Go to Step
4
|
4
|
- Turn the headlamp switch to the auto position.
- Turn the ignition OFF.
- Disconnect the BCM.
- Turn the headlamp switch to the ON position.
- 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
6
|
5
|
- Reconnect the BCM if the BCM was disconnected in a previous step.
- Turn the ignition ON.
- 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
7
| Go to
Diagnostic System Check - Body Control System
in Body Control System
|
6
| Locate and
repair the open in CKT 352 (WHT) between the underhood bussed electrical center
(UBEC) and the BCM.
Is the repair complete?
| --
| System OK
| --
|
7
|
- Ensure the headlamp switch is in the auto position.
- Using the scan tool, command the headlamps ON.
Do the headlamps come on?
| --
| Go to
Headlight System Check
|
Go to Step 8
|
8
| Replace the BCM. Refer to
Body Control Module Replacement
in Body Control System.
Is the repair complete?
| --
| System OK
| --
|
