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+ | 1, 3 | 1 | -- | -- |
LR Window Switch B+ | 1, 3 | 3 | -- | -- |
Front Passenger Door Module B+ | 2, 4 | 2 | -- | -- |
RR Window Switch B+ | 2, 4 | 4 | -- | -- |
Power Window Switch Right Rear Down Signal | B3823 | B3823 | B3823 | -- |
Power Window Switch Right Rear Up Signal | B3822 | B3822 | B3822 | -- |
Power Window Switch Left Rear Down Signal | B3820 | B3820 | B3820 | -- |
Power Window Switch Left Rear Up Signal | B3819 | B3819 | B3819 | -- |
Power Window Lockout Left Rear Control | B3821 | B3821 | B3821 | -- |
Power Window Lockout Right Rear Control | B3824 | B3824 | B3824 | -- |
LR Window Motor Control | 3 | 3 | 3 | -- |
Passenger Window Motor Control | 2 | 2 | 2 | -- |
RR Window Motor Control | 4 | 4 | 4 | -- |
Driver Window Motor Control | 1 | 1 | 1 | -- |
LR Window Switch Ground | -- | 3 | 3 | -- |
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 and the driver master control. 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 switch (DDS).
Conditions for Running the DTC
Battery voltage is between 9-16 volts.
Conditions for Setting the DTC
B3821
The BCM detects a fault in the left rear window lockout circuit.
B3824
The BCM detects a fault in the right rear window lockout circuit.
Action Taken When the DTC Sets
The left or right rear power window will be inoperative.
Conditions for Clearing the DTC
| • | The DTC will be current for as long as the fault is present. |
| • | When the fault is no longer present, the DTC will be a history DTC. |
| • | A history DTC will clear after 50 ignition cycles. |
Reference Information
Schematic Reference
Connector End View Reference
Description and Operation
Power Windows Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Verification
Ignition ON, command the rear windows UP and DOWN by using the window switches on the driver master control and their respective rear window switches. The rear windows should perform the UP and DOWN function from each switch.
Circuit/System Testing
- Ignition OFF, disconnect the harness connector at the appropriate rear window switch.
- Ignition ON, with the rear window switches enabled, test for greater than 10 volts between the control circuit terminal D and ground.
- If all circuits test normal, replace the rear window switch.
| ⇒ | If less than the specified range, test the control circuit for a short to ground or 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 |
