• | 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 | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
---|---|---|---|---|
B+ -- Headlamp Washer Relay | 1 | 1 | -- | -- |
Headlamp Washer Relay Control | 1 | 1 | 2 | -- |
Headlamp Washer Fluid Pump Control | 1 | 1 | 2 | -- |
Headlamp Washer Relay Ground | -- | 1 | -- | -- |
Headlamp Washer Fluid Pump Ground | -- | 1 | -- | -- |
1. Headlamp washer pump inoperative 2. Headlamp washer pump always on |
When the washer switch is pressed, the windshield wiper switch sends a voltage signal through windshield washer switch signal circuit to the wiper motor module and the body control module (BCM) indicating the wash command. Every fourth time the windshield washer system is commanded ON, the BCM will initiate a headlamp wash cycle by applying B+ to the headlamp washer relay control circuit energizing the relay. The relay then closes its switch contacts applying B+ through the headlamp washer pump motor control circuit to the headlamp washer pump motor. The pump motor then runs spraying washer fluid on the headlamps. A headlamp wash cycle consists of a prewash, then a pause, and then a wash operation.
Headlamp Washer System Description and Operation
Control Module References for scan tool information
⇒ | If not above the minimum level, fill the reservoir and inspect for leaks. |
⇒ | If greater than the specified range, test the ground circuit for an open/high resistance. |
⇒ | If the test lamp does not illuminate, test the HEADLAMP Circuit fuse for an open.. |
⇒ | If the test lamp illuminates, test the control circuit for a short to voltage. |
⇒ | If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the BCM. |
⇒ | If the test lamp is always OFF, test the control circuit for a short to ground or open/high resistance. If the circuit tests normal, replace the BCM. |
⇒ | If greater than the specified range, test the ground circuit for an open/high resistance. |
⇒ | If it does not activate, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the headlamp washer fluid pump. |
⇒ | If the headlamp washer fluid pump does not activate, replace the washer fluid pump. |
⇒ | If the resistance is not within the specified range, replace the relay. |
• | 30 and 86 |
• | 30 and 87 |
• | 30 and 85 |
• | 85 and 87 |
⇒ | If not the specified value, replace the relay. |
⇒ | If greater than the specified range, replace the relay. |
⇒ | If greater than the specified range, replace the relay. |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
• | Control Module References for BCM replacement, programming, and setup |