For 1990-2009 cars

### 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
--- | --- | --- | --- | ---
B+ | 1 | 1 | -- | --
Ignition Voltage | 1 | 1 | -- | --
Heated Washer Fluid Control Switch Signal | 1 | 1 | 1 | --
Windshield Washer Switch Signal | 4 | 1 | 4 | --
Heated Washer Fluid Indicator Signal | 3 | 2 | 2 | --
Washer Solvent Heater Assembly Ground | -- | 1 | -- | --
Washer Solvent Heater Assembly Logic Ground | -- | 1 | -- | --
1. Windshield Washer Solvent Heater Malfunction 2. Windshield Washer Solvent Heater Indicator Inoperative 3. Windshield Washer Solvent Heater Indicator Always ON 4. Windshield Wiper System Malfunction

### Circuit/System Description

The windshield washer solvent heater operates along side the standard windshield wiper washer system. When a heated washer cycle is activated, the solvent heater controls the windshield washers through the windshield washer switch signal circuit. The windshield heated washer fluid module is supplied with high current power and ground circuits that are used to energize the heater coils. The low current logic voltage is supplied to the module through the body control module (BCM). The heated washer cycle operation is activated by the windshield wiper/washer switch. When the heated washer fluid switch is pressed, the heated wash switch signal circuit is momentarily grounded and the heated washer cycle is activated. During the heated wash cycle the 3 heater elements in the solvent heater are energized, and when the solvent temperature reaches approximately 70°C (160°F) the heater grounds the washer switch signal circuit until the heated solvent is dispensed. The heated washer cycle will run 4 heat and wash actions unless deactivated by the heated washer switch.

### Reference Information

#### Schematic Reference

Wiper/Washer Schematics

#### Connector End View Reference

Component 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

Control Module References for scan tool information

### Circuit/System Verification

1. Ignition ON, verify the washers operate using the washer switch.

⇒ | If the base washer system does not operate, refer to Windshield Wiper Washer System Malfunction.

2. Depress the heated washer switch. The heater washer fluid system should begin to cycle and the heated washer indicator lamp illuminates while the system is performing the wipe/wash cycle

⇒ | If the heated washer fluid system does not begin to cycle, refer to Windshield Washer Solvent Heater Malfunction.

⇒ | If the heated washer indicator lamp does not illuminate, refer to Heated Washer Fluid Indicator Malfunction.

### Circuit/System Testing

#### Windshield Washer Solvent Heater Malfunction

1. Ignition OFF, disconnect the X1 harness connector at the windshield heated washer fluid module.
2. Test for less than 5 ohms between the ground circuit terminal 2 and ground.

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

3. Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal 1 and ground.

⇒ | If the test lamp does not illuminate, test the B+ circuit for an open/high resistance. If the circuit fuse is open, test the B+ circuit for a short to ground. If the circuit test normal, replace the windshield heated washer fluid module.

4. Ignition OFF, connect the X1 harness connector at the windshield heated washer fluid module. Disconnect the X2 harness connector at the windshield heated washer fluid module.
5. Test for less than 5 ohms between the ground circuit terminal 4 and ground.

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

6. Ignition ON, verify that a test lamp illuminates between the ignition circuit terminal 6 and ground.

⇒ | If the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance. If the circuit tests normal, refer to Power Mode Mismatch.

7. Verify the scan tool Windshield Washer Switch parameter displays Inactive.

⇒ | If not the specified value, test the signal circuit terminal 5 for a short to ground. If the circuit tests normal, refer to Windshield Wiper Washer System Malfunction.

8. Install a 3A fused jumper wire between the signal circuit terminal 5 and ground. Verify the scan tool Windshield Washer Switch parameter displays 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, refer to Windshield Wiper Washer System Malfunction.

9. Ignition OFF, connect a test lamp between the signal circuit terminal 1 and B+.
10. Command the heated washer system ON and OFF using the heated washer switch. The test lamp should turn ON and OFF when changing between the commanded states.

⇒ | If the test lamp is always ON, test the signal circuit for a short to ground. If the circuit tests normal, test or replace the windshield wiper/washer switch.

⇒ | If the test lamp is always OFF, test the signal circuit for a short to voltage or and open/high resistance. If the circuit tests normal, test or replace the windshield wiper/washer switch.

11. If all circuits test normal, test or replace the windshield heated washer fluid module.

#### Heated Washer Fluid Indicator Malfunction

1. Ignition OFF, disconnect the X2 harness connector at the windshield heated washer fluid module.
2. Verify the heated washer fluid indicator lamp is not illuminated.

⇒ | If the lamp is illuminated, test the signal circuit terminal 2 for a short to ground. If the circuit tests normal, replace the IPC.

3. Ignition ON, install a 3A fused jumper wire between the signal circuit terminal 2 and ground. Verify the heated washer fluid indicator lamp is not illuminated.

⇒ | If the lamp is illuminated, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the IPC.

4. If all circuits test normal, test or replace the windshield heated washer fluid module.

### Component Testing

#### Heated Washer Fluid Switch

1. Ignition OFF, disconnect the harness connector at the windshield wiper/washer switch.
2. Test for infinite resistance between the signal terminal 8 and the ground terminal 7 with the switch in the open position.

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

3. Test for less than 3 ohms between the signal terminal 10 and the ground terminal 8 with the switch in the closed position.

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

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• | Headlamp Switch Replacement

• | Windshield Washer Solvent Heater Replacement