Diagnostic Routine D

Diagnostic Routine D

Diagnostic Overview

The Wiper Stays On Continuously - Rear Window

Refer to Wiring Diagram Set 81 for schematic and connector information Electrical Diagrams.

Normal Operation and Fault Conditions

REFER to Rear Wiper Operation . A failure of the rear wiper relay, a short to ground on the rear wiper relay control circuit or a short to voltage on the rear wiper relay output circuit causes the rear wiper to operate continuously.

DTC Fault Trigger Conditions






Pinpoint Test

1. CHECK FOR BCM (Body Control Module) DTCs (Diagnostic Trouble Codes)

1. Ignition ON.

2. Using a scan tool, carry out the BCM (Body Control Module) self-test.

Are any BCM (Body Control Module) DTCs (Diagnostic Trouble Codes) present?







2. CHECK THE BCM (Body Control Module) WIPER/WASHER SWITCH PIDs (Parameter Identifications)

1. Using a scan tool, view the following BCM (Body Control Module) PIDs (Parameter Identifications):

- Wiper Stalk Illegal Combination (WPR_SW_ICOM)
- Wiper Stalk Stuck Position or Button (WPR_SW_STK)

2. While monitoring the PIDs (Parameter Identifications), place the wiper/washer switch into each rear window position (OFF, LOW, INT).

Does either PID (Parameter Identification) display TRUE at any time?







3. CHECK THE REAR WIPER RELAY

1. Ignition OFF.

2. Remove the Rear Wiper Relay.

3. Carry out the Relay-Micro ISO (International Organization for Standardization) component test.

Did the relay pass the test?







4. CHECK THE REAR WINDOW WIPER MOTOR RELAY INPUT CIRCUIT FOR A SHORT TO VOLTAGE

1. Ignition OFF.

2. Disconnect the Rear Window Wiper Motor electrical connector.

3. Ignition ON.

4. Measure:





Is any voltage present?







5. CHECK THE REAR WIPER RELAY CONTROL CIRCUIT FOR A SHORT TO GROUND

1. Ignition OFF.

2. Remove the Rear Wiper Relay.

3. Disconnect BCM (Body Control Module) C2280B.

4. Measure:





Is the resistance greater than 10,000 ohms?







6. CHECK FOR CORRECT BCM (Body Control Module) OPERATION

1. Ignition OFF.

2. Disconnect and inspect all BCM (Body Control Module) electrical connectors.

3. Repair:

- corrosion (install new connector or terminal - clean module pins)
- damaged or bent pins - install new terminals/pins
- pushed-out pins - install new pins as necessary

4. Connect all the BCM (Body Control Module) electrical connectors. Make sure they seat and latch correctly.

5. Connect the Rear Window Wiper Motor electrical connector.

6. Operate the system and determine if the concern is still present.

Is the concern still present?