For 1990-2009 cars

## Washer Malfunction Front

### 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.

### Diagnostic Fault Information

Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance
--- | --- | --- | --- | ---
Windshield Washer Switch Signal | 2 | 1 | 1 | --
Windshield Washer Fluid Pump Control | 1 | 1 | 2 | --
Windshield Washer Relay Control | 2 | 1 | B3873 00 | --
Windshield Washer Fluid Pump Ground | -- | 1 | -- | --
1. Washer Inoperative 2. Washers Always ON

### Circuit/System Description

The body control module (BCM) controls the washer motor based on an input from the windshield wiper washer switch. The BCM monitors the washer switch through the windshield washer switch signal circuit. When the WASH switch is closed, ground is supplied to the windshield washer switch signal circuit. When this is seen, the BCM will command the windshield washer fluid pump and the low speed wipers on.

### Reference Information

#### Schematic Reference

Wiper/Washer Schematics

#### Connector End View Reference

Wiper/Washer Connector End Views

#### Description and Operation

Wiper/Washer System Description and Operation

#### Electrical Information Reference

• | Circuit Testing

• | Connector Repairs

• | Testing for Intermittent Conditions and Poor Connections

• | Wiring Repairs

#### Scan Tool Reference

• | Scan Tool Output Controls

• | Scan Tool Data List

• | Scan Tool Data Definitions

### Circuit/System Verification

1. Ignition ON, wiper switch in the OFF position, observe the scan tool Windshield Washer Switch parameter while cycling the WASH switch ON and OFF. The parameter should cycle between Active and Inactive.

⇒ | If the parameter does not cycle between the specified values, refer to Windshield Wiper Switch Circuit Malfunction.

2. Operate the washers using the WASH switch. Verify the washer pump activates and the low speed wipers turn on.

⇒ | If the washer pump does not activate, refer to Washer Pump Circuit Malfunction.

⇒ | If the low speed wipers do not turn on, refer to Windshield Wiper System Malfunction .

### Circuit/System Testing

#### Windshield Wiper Switch Circuit Malfunction

1. Ignition OFF, disconnect the harness connector at the windshield wiper switch.
2. Ignition OFF, test for less than 20 ohms of resistance between the ground circuit terminal D and ground.

⇒ | If greater than the specified range, test the ground circuit for an open/high resistance. If the circuit test normal, replace the BCM.

3. Ignition ON, verify the scan tool Windshield Washer Switch parameter is Inactive.

⇒ | If not the specified value, test the signal circuit terminal B for a short to ground. If the circuit tests normal, replace the BCM.

4. Install a 3A fused jumper wire between the signal circuit terminal B and ground. Verify the scan tool Windshield Washer Switch parameter is Active.

⇒ | 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.

5. If all circuits test normal, test or replace the windshield wiper washer switch.

#### Washer Pump Circuit Malfunction.

1. Ignition OFF, disconnect the C3 harness connector at the underhood fuse block.
2. Connect a test lamp between the control circuit terminal 25 and B+.
3. Ignition ON, command the washers ON and OFF using the WASH switch. The test lamp should turn ON and OFF when changing between the commanded states.

⇒ | If the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the BCM.

⇒ | If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the BCM.

4. Ignition OFF, connect the C3 harness connector at the underhood fuse block. Disconnect the harness connector at the washer pump.
5. Test for less than 20 ohms of resistance between the ground circuit terminal 1 and ground.

⇒ | If greater than the specified range, test the ground circuit for an open/high resistance.

6. Connect a test lamp between the control circuit terminal 2 and ground.
7. Ignition ON, command the washers ON and OFF using the WASH switch. The test lamp should turn ON and OFF when changing between the commanded states.

⇒ | If the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the underhood fuse block.

⇒ | If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the underhood fuse block.

8. If all circuits test normal, test or replace the washer pump.

### Component Testing

#### Windshield Wiper Washer Switch

1. With the WASH switch in the open position, test for infinite resistance between the ground terminal D and the signal terminal B.

⇒ | If not the specified value, replace the windshield wiper washer switch.

2. With the WASH switch in the closed position, test for less than 2 ohms of resistance between the ground terminal D and the signal terminal B.

⇒ | If greater than the specified range, replace the windshield wiper washer switch.

#### Washer Pump

1. Ignition OFF, disconnect the harness connector at the washer pump.
2. Install a 10A fused jumper wire between the control terminal 2 and 12 volts. Install a jumper wire between the ground terminal 1 and ground.
3. Verify the washer pump is activated.

⇒ | If the washer pump does not activate , replace the washer pump.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure

• | Washer Pump Replacement

• | Underhood Electrical Center or Junction Block Replacement

• | Control Module References for BCM replacement, setup, and programming

## Washer Malfunction Rear

### 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.

### Circuit/System Description

The rear washer is controlled based on an input from the rear wiper/washer switch. When the wiper portion of the rear wiper/washer switch is closed, a ground signal is provided to the RR WASH PCB relay indicating rear washer operation is requested. With ground provided to the RR WASH PCB relay coil, the relay is energized and B+ is supplied to the washer pump.

### Reference Information

#### Schematic Reference

Wiper/Washer Schematics

#### Connector End View Reference

Wiper/Washer Connector End Views

#### Description and Operation

Wiper/Washer System Description and Operation

#### Electrical Information Reference

• | Circuit Testing

• | Connector Repairs

• | Testing for Intermittent Conditions and Poor Connections

• | Wiring Repairs

#### Scan Tool Reference

• | Scan Tool Output Controls

• | Scan Tool Data List

• | Scan Tool Data Definitions

### Circuit/System Verification

1. Ignition ON, verify the rear wiper operates using the rear wiper/washer switch.

⇒ | If the rear wiper does not operate, refer to Windshield Wiper System Malfunction.

2. Command the rear washer ON using the rear wiper/washer switch. The rear washer should activate.

### Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the rear window wiper motor.
2. Ignition ON, test for B+ between the signal circuit terminal E and ground.

⇒ | If less the specified value, test the signal circuit for a short to ground or an open/high resistance.

3. Rear washer switch closed, test for less than 10 ohms of resistance between the signal circuit terminal E and ground.

⇒ | If greater than the specified range, test the signal circuit for an open/high resistance. If the circuit tests normal, test or replace the rear wiper/washer switch.

4. Ignition OFF, connect the harness connector at the rear window wiper motor. Disconnect the harness connector at the windshield washer pump.
5. Test for less than 20 ohms of resistance between the ground circuit terminal 2 and ground.

⇒ | If greater than the specified range, test the ground circuit for an open/high resistance.

6. Install a test lamp between the control circuit terminal 1 and the ground circuit terminal 2.
7. Ignition ON, command the rear washer ON using the rear wiper/washer switch. The test lamp should illuminate.

⇒ | If the test lamp does not illuminate, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the underhood fuse block.

8. If all circuits test normal, test or replace the windshield washer pump.

### Component Testing

#### Rear Wiper/Washer Switch

1. With the rear washer switch in the open position, test for infinite resistance between the ground terminal 1 and the signal terminal 2.

⇒ | If not the specified value, replace the rear wiper/washer switch.

2. With the rear washer switch in the closed position, test for less than 2 ohms of resistance between the ground terminal 1 and the signal terminal 2.

⇒ | If not within the specified range, replace the rear wiper/washer switch.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure

• | Washer Pump Replacement

• | Underhood Electrical Center or Junction Block Replacement