Diesel Data: Automotive Repair

Washers Run Continuously With Ignition on







POSSIBLE CAUSES
- Multi-function switch
- Washer pump motor control circuit short to voltage
- Body control module

Diagnostic Test




1. MEASURE MULTI-FUNCTION SWITCH VOLTAGE

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

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

NOTE: Check connectors - Clean/repair as necessary.

Connect a fused jumper wire from B(+) to cavity 11 of the Multi-Function Switch.
Measure the voltage of the Washer Pump Motor Control circuit at the Multi-Function Switch harness connector.

Q: Is voltage present?

YES: Replace the Multi-Function Switch. Perform BODY VERIFICATION TEST. Verification Tests
NO: Go to 2




2. MEASURE WASHER PUMP MOTOR CIRCUIT VOLTAGE

Disconnect the Washer Pump Motor harness connector. Disconnect the BCM harness connector.

NOTE: Check connectors - Clean/repair as necessary.

Turn the ignition on.
Measure the voltage of the Washer Pump Motor Control circuit at cavity 8 of the Multi-Function Switch harness connector.

Q: Is voltage present?

YES: Repair the Washer Pump Motor Control circuit for a short to voltage. Perform BODY VERIFICATION TEST. Verification Tests
NO: Replace the Body Control Module. Perform BODY VERIFICATION TEST. Verification Tests