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 Descriptor
DTC B3922 00: Front Wiper Function Select CircuitDiagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
WPR HI Relay B+ | 1, 2 | 1, 2 | -- | -- |
Windshield Wiper Switch Signal | B3922 00 | 1 | 1 | -- |
Windshield Wiper Switch High Signal | 4 | 2 | 2 | -- |
Windshield Wiper Motor Park Switch Signal | 3 | 3 | -- | -- |
WPR Relay Control | B3715 02 | 1 | 4 | -- |
WPR HI Relay Control | 4 | 2 | B3875 00 | -- |
Windshield Wiper Motor High Speed Control | 2 | 2 | 4 | -- |
Windshield Wiper Motor Low Speed Control | 1 | 1 | 4 | -- |
Windshield Wiper Switch Low Reference | -- | 1, 2 | 1, 2 | -- |
Windshield Wiper Motor Ground | -- | 1, 2, 3 | -- | -- |
WPR Relay Ground | -- | 1 | -- | -- |
1. Delay or Low Speed Wipers Inoperative 2. High Speed Wipers Inoperative 3. Wipers Do Not Park 4. Wipers Always ON | ||||
Circuit/System Description
The body control module (BCM) controls the wiper motor based on input from the windshield wiper washer switch. The BCM monitors the wiper washer switch through three separate signal circuits and a ground circuit. The windshield wiper switch high signal circuit is used to determine high speed wiper operation, the windshield wiper switch low signal is used to determine low speed, intermittent, and mist operation through the use of a resistor ladder, and windshield washer switch signal circuit is used to determine washer operation.
Conditions for Running the DTC
The ignition is ON.
Conditions for Setting the DTC
The BCM detects a short to ground on the windshield wiper switch low signal circuit.
Action Taken When the DTC Sets
The BCM will only operate the windshield wipers in the high speed mode.
Conditions for Clearing the DTC
| • | A current DTC will clear when the condition for setting the fault is no longer seen. |
| • | A history DTC will clear after 50 consecutive ignition cycles without a fault present. |
Reference Information
Schematic Reference
Connector End View Reference
Description and Operation
Wiper/Washer System Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Verification
- Wiper switch in the LO position, verify the scan tool Windshield Wiper Switch parameter is Low.
- Wiper switch in the HIGH position, verify the scan tool Wiper High Speed Switch parameter is Active
- Wiper switch in the INT position, verify the scan tool Windshield Wiper Switch parameter is Intermittent.
- Wiper switch in the INT position, observe the scan tool Wiper Delay Setting parameter while cycling the delay adjustment switch from long delay to short delay. The parameter should cycle between D1 and D5 as each delay position is selected.
Circuit/System Testing
- Ignition OFF, disconnect the X1 harness connector at the multifunction switch.
- Ignition OFF, test for less than 20 ohms between the low reference circuit terminal 7 and ground.
- Ignition ON, verify the scan tool Windshield Wiper Switch parameter is Off.
- Install a 3A fused jumper wire between the signal circuit terminal 4 (with W49) or terminal 10 (without W49) and ground. Verify the scan tool Windshield Wiper Switch parameter is Switch Fault.
- If all circuits test normal, test or replace the multifunction switch.
| ⇒ | If greater than the specified range, test the ground circuit for an open/high resistance. If the circuit test normal, replace the BCM. |
| ⇒ | If not the specified value, test the signal circuit terminal 4 (with W49) or terminal 10 (without W49) for a short to ground. If the circuit tests normal, replace the BCM. |
| ⇒ | If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the BCM. |
Component Testing
- Ignition OFF, disconnect the X1 harness connector at the multifunction switch.
- With the wiper switch in the HIGH position, test for less than 2 ohms between the low reference terminal 7 and the signal terminal 5 (with W49) or terminal 9 (without W49).
- While cycling the wiper switch through each delay and speed position, test for the specified resistance between the low reference terminal 7 and the signal terminal 4 (with W49) or terminal 10 (without W49).
Important: If the switch tests open in any switch position other than Off, test the signal circuits for a short to voltage before replacing the switch.
| ⇒ | If greater than the specified range, replace the windshield wiper washer switch. |
Switch Position | Resistance |
|---|---|
Off | Infinite |
Mist | 300-364 Ω |
Delay 1 | 3.48k-4.25k Ω |
Delay 2 | 2.52k-3.08k Ω |
Delay 3 | 1.78k-2.18k Ω |
Delay 4 | 1.17k-1.44k Ω |
Delay 5 | 697-851 Ω |
Low | 300-364 Ω |
High | 300-364 Ω |
| ⇒ | If any switch position is not within the specified range, replace the multifunction switch. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for BCM replacement, setup, and programming |
