Diesel Data: Automotive Repair

Washers Inoperative







POSSIBLE CAUSES
- Multi-function switch
- Washer pump motor control circuit open
- Washer pump motor

Diagnostic Test




1. MEASURE WASHER PUMP MOTOR CIRCUIT RESISTANCE

NOTE: If any BCM DTCs are set, diagnose them first before continuing.

Turn the ignition off.
Disconnect the Multi-Function Switch harness connector. Disconnect the Washer Pump Motor harness connector.

NOTE: Check connectors - Clean/repair as necessary.

Connect a jumper wire between cavity 1 and cavity 2 of the Washer Pump Motor harness connector.
Measure the resistance between ground and the Washer Pump Motor Control circuit at cavity 8 of the Multi-Function Switch harness connector.

Q: Is the resistance below 5.0 ohms?

YES: Go to 2
NO: Repair the Washer Pump Motor Control circuit for an open. Perform BODY VERIFICATION TEST. Verification Tests




2. MEASURE MULTI-FUNCTION SWITCH VOLTAGE

Disconnect the jumper wire.
Connect the Multi-Function Switch harness connector.
Turn the ignition on.
Depress the washer switch, and measure the voltage of the Washer Pump Motor Control circuit at the Washer Pump Motor Connector.

Q: Is the voltage above 10 volts?

YES: Replace the Washer Pump Motor. Perform BODY VERIFICATION TEST. Verification Tests
NO: Replace the Multi-Function Switch. Perform BODY VERIFICATION TEST. Verification Tests