Circuit Description
The SBM controls the courtesy lamps for theater dimming. The outputs will fade out in order to turn the lamps to the OFF position. If there is an open or a short to ground in CKT 156, a fault condition is present and a DTC will set.
Conditions for Setting the DTC
The SBM detects a short to ground or an open in CKT 156.
Action Taken When the DTC Sets
| • | Stores a DTC B2452 in the SBM memory |
| • | No driver warning message will be displayed for this DTC. |
Conditions for Clearing the DTC
| • | A short to ground is no longer detected by the SBM in CKT 156. |
| • | An open is no longer detected by the SBM in CKT 156. |
| • | A history DTC clears after 50 consecutive ignition cycles if the condition for the fault is no longer present. |
| • | Using the on-board diagnostic (clearing DTCs) feature. |
| • | Using a scan tool. |
Diagnostic Aids
The following conditions may cause an intermittent malfunction to occur:
| • | An intermittent short to ground in CKT 156 |
| • | An intermittent open in CKT 156 |
| • | A short to ground or an open internally to the SBM |
If the DTC is a history DTC, the problem may be intermittent. Perform the tests shown while wiggling the wiring and the connectors. This can often cause the malfunction to appear.
Test Description
The number(s) below refer to the step number(s) on the diagnostic table.
-
Always perform the SBM Diagnostic System Check before attempting to diagnose a DTC B2452.
-
This test inspects for a short to ground in CKT 156 (WHT).
-
This test inspects for an open in CKT 156 (WHT).
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
Did you perform the Body Control Module (SBM) Diagnostic System Check ? | -- | Go to Step 2 | ||
Is there continuity to ground in CKT 156? | -- | Go to Step 3 | Go to Step 4 | |
3 | Repair the short to ground in CKT 156 (WHT). Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Step 7 | -- |
Connect a J 39200 DMM from cavity C14 to cavity C4 of CKT 156 (WHT). Is there continuity in CKT 156? | -- | Go to Step 5 | Go to Step 6 | |
5 |
Is the SBM replacement complete? | -- | Go to Step 7 | -- |
6 | Repair a poor connection or open in CKT 156 (WHT). Refer to Wiring Repairs in Wiring Systems. Is the circuit repair complete? | -- | Go to Step 7 | -- |
7 |
Are all of the DTCs cleared? | -- | -- |
