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 provide an overview of each diagnostic category. |
DTC Descriptors
DTC B320A 39: Front Door Window Motor Internal Electronic Failure / DiscardDTC B320A 4B: Front Door Window Motor Calibration Not Learned
DTC B320A 42: Front Door Window Motor Calibration Data Set Not Programmed
DTC B320B 39: Rear Door Window Motor Internal Electronic Failure / Discard
DTC B320B 4B: Door Window Motor Calibration Not Learned
DTC B320B 42: Rear Door Window Motor Calibration Data Set Not Programmed
Diagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
Rear Window Switch Signal - LR | 1 | 1 | 1 | -- |
Rear Window Switch Signal - RR | 1 | 1 | 1 | -- |
Rear Window Switch Voltage Supply - LR | 1 | 1 | 1 | -- |
Rear Window Switch Voltage Supply - RR | 1 | 1 | 1 | -- |
Window Motor Voltage Supply - LF | 1 | 1 | -- | -- |
Window Motor Voltage Supply - LR | 1 | 1 | -- | -- |
Window Motor Voltage Supply - RF | 1 | 1 | -- | -- |
Window Motor Voltage Supply - RR | 1 | 1 | -- | -- |
Rear Window Switch Ground - LR | -- | 1 | -- | -- |
Rear Window Switch Ground - RR | -- | 1 | -- | -- |
Window Motor Ground - LF | -- | 1 | -- | -- |
Window Motor Ground - LR | -- | 1 | -- | -- |
Window Motor Ground - RF | -- | 1 | -- | -- |
Window Motor Ground - RR | -- | 1 | -- | -- |
1. Power Windows Malfunction | ||||
Circuit/System Description
The front and rear power windows are controlled by the driver door module (DDM) and front passenger door module (PDM). The DDM and PDM each contain power window switches that are integrated into the module. The DDM contains the master power window switch that controls all power window operations. The DDM supplies the left rear power window switch with a 12-volt reference and signal circuit. The power window switch contained in the PDM controls the front passenger window operation only. The PDM supplies the right rear power window switch with a 12-volt reference and signal circuit.
When the driver power window switch is activated to a desired position, the DDM examines the request and checks for messages from other vehicle control modules prohibiting window movement. If no prohibitive messages have been received, the DDM will send a LIN serial data message to the driver door window motor to move the window to the desired position.
When the DDM receives a request to operate one of the right side passenger windows from the master switch, a GMLAN serial data message is sent to the PDM. The PDM examines the request and checks for messages from other vehicle control modules prohibiting the window movement. If no prohibitive messages have been received, the PDM will send a LIN serial data message to the appropriate window motor to move the window as requested.
The DDM and PDM supply there respective rear power window switches with a 12-volt reference and signal circuit. The rear power window switches contain separate resistors for each switch position. When a rear power window switch is activated, the associated door control module interprets the signal and checks for messages from other vehicle control modules prohibiting the window movement. If no prohibitive messages have been received, the door control module sends a LIN serial data message to the appropriate power window motor commanding the requested window position. For more detailed information concerning power window operation refer to Power Windows Description and Operation.
Conditions for Running the DTC
Battery voltage must be between 9-16 volts.
Conditions for Setting the DTC
B320A 39, B320B 39
An internal malfunction or a momentary voltage spike has been detected by the DDM or PDM in the front power window motor while commanding the window UP/DOWN.
B320A 42, B320B 42
A not normalized/programmed driver or front passenger door power window motor.
B320A 4B, B320B 4B
The front window motor experiences a loss of voltage in the B+ circuit or an open/high resistance in the serial data circuit.
Action Taken When the DTC Sets
The appropriate power window malfunction
Conditions for Clearing the DTC
B320A 39, B320B 39
If the DTC is current, the appropriate window motor must be replaced before the DTC can be cleared.
B320A 42, B320B 42
The affected power window motor must be programmed before the DTC can be cleared.
B320A 4B, B320B 4B
The affected power window motor must be calibrated before the DTC can be cleared.
Reference Information
Schematic Reference
Connector End View Reference
Window Systems Connector End Views
Electrical Information Reference
Scan Tool Reference
Circuit/System Testing
B320A 39 or B320B 39
Ignition ON, command the appropriate power window DOWN and UP with a scan tool. The power window should go DOWN and UP as commanded.
| ⇒ | If the DTC is current and the power window is inoperative, replace the power window motor. |
| ⇒ | If the DTC is history and the power window performs the UP and DOWN functions, clear the DTC. |
B320A 42 or B320B 42
Ignition ON, reprogram the appropriate power window and operate the power window within the conditions for running the DTC, verify the DTC does not reset.
| ⇒ | If the DTC resets, replace the power window motor. |
B320A 4B or B320B 4B
Ignition ON, command the appropriate power window motor fully DOWN by pressing and holding the window switch for 5 seconds, then command the power window motor fully UP by lifting and holding the window switch for 5 seconds. Operate the power window within the conditions for running the DTC, verify the DTC does not reset
| ⇒ | If the DTC resets, replace the power window motor. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for power window motor replacement, setup and programming |
