Diagnostic Instructions
| • | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
| • | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
| • | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
DTC Descriptors
DTC B3821: Left Rear Window Relay Power CircuitDTC B3824: Right Rear Window Relay Power Circuit
Diagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
Driver Door Module B+ | U0199 | U0199 | -- | -- |
Driver Window Motor B+ | U1511, B320A 4B | U1511, B320A 4B | -- | -- |
LR Window Switch B+ | 1, 2, 3, 4 | 3 | -- | -- |
Passenger Door Module B+ | 2 | 2 | -- | -- |
Passenger Window Motor B+ | 1, 2, 3, 4 | 2 | -- | -- |
RR Window Switch B+ | 1, 2, 3, 4 | 4 | -- | -- |
Driver Window Motor Serial Data | U1511, B320A 4B | U1511, B320A 4B | 1 | -- |
Passenger Window Motor Serial Data (AXC) | 2 | 2 | 2 | -- |
LR Window Motor Control | 3 | 3 | 3 | -- |
Passenger Window Motor Control (AXE) | 2 | 2 | 2 | -- |
RR Window Motor Control | 4 | 4 | 4 | -- |
Window Master Switch LR Down Control | B3820 | B3820 | B3820 | -- |
Window Master Switch Lockout Control | B3821, B3824 | B3821, B3824 | B3821, B3824 | -- |
Window Master Switch LR Up Control | B3819 | B3819 | B3819 | -- |
Window Master Switch RR Down Control | B3823 | B3823 | B3823 | -- |
Window Master Switch RR Up Control | B3822 | B3822 | B3822 | -- |
Driver Door Module Ground | -- | U0199 | U0199 | -- |
LR Window Switch Ground | -- | 3 | 3 | -- |
Driver Window Motor Ground | -- | U1511 | U1511 | -- |
Passenger Door Module Ground | -- | 2 | 2 | -- |
Passenger Window Motor Ground (AXC) | -- | 2 | 2 | -- |
RR Window Switch Ground | -- | 4 | 4 | -- |
1. Driver Window Malfunction 2. Passenger Window Malfunction 3. Left Rear Window Malfunction 4. Right Rear Window Malfunction | ||||
Circuit/System Description
The body control module (BCM) supplies voltage to the rear window switches allowing for normal window operation from the rear switches. If the rear window lockout function is enabled, the BCM will not supply voltage to the rear window switches and the rear windows will only operate when the BCM receives a command to operate the appropriate rear window UP or DOWN from the driver door module (DDM).
Conditions for Running the DTC
| • | Battery voltage is between 9-16 volts. |
| • | The ignition switch is in the ON position. |
| • | The window lockout function is disabled. |
Conditions for Setting the DTC
B3821
The left rear window lockout circuit is shorted to ground.
B3824
The right rear window lockout circuit is shorted to ground.
Action Taken When the DTC Sets
The left or right rear power window will be inoperative.
Conditions for Clearing the DTC
| • | When the fault is no longer present the DTC will be a history status code. |
| • | The history code will clear after 50 fault free ignition cycles or by using the scan tool clear DTCs feature. |
Reference Information
Schematic Reference
Connector End View Reference
Window Systems Connector End Views
Description and Operation
Power Windows Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for Scan Tool Information
Circuit/System Testing
- Ignition OFF, disconnect the harness connector at the appropriate rear window switch.
- Ignition ON, connect a test lamp between the power window lockout control circuit terminal D and ground.
- Command the Rear Window Lockout parameter ON and OFF by pressing the rear lockout switch on the driver master control. The test lamp should turn ON and OFF when changing between the commanded states.
- If all circuits test normal, replace the appropriate rear window switch.
| ⇒ | If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for BCM replacement, setup and programming |
