The headlamp washer switch signal circuit is supplied a 12-volt reference through a resistor then monitored within the body control module (BCM). The headlamp washer switch is open when in an inactive state. When the headlamp washer switch is activated the signal circuit is closed to ground. When the headlamp washer switch signal circuit is closed to ground the reference voltage is dropped across the resistor within the BCM. The low voltage on the headlamp washer switch signal circuit indicates to the BCM the switch status is active.
• | Battery voltage must be between 9-16 volts. |
• | The headlamp washer switch is active. |
The headlamp washer switch signal to the BCM is low longer than 10 seconds.
• | The DTC will be current for as long as the fault is present. |
• | The headlamp washers will be disabled for as long as the DTC is current. |
• | The DTC status will change form current to history when the fault is no longer present. |
• | A history DTC will be cleared after 100 error free ignition cycles. |
The numbers below refer to the step numbers on the diagnostic table.
This step verifies that the fault is current.
This step verifies the switch input to the BCM.
This step determines if the fault is in the headlamp washer switch. If the switch input to the BCM changes to an inactive state when disconnected the switch contacts are stuck or shorted to ground.
Step | Action | Yes | No |
---|---|---|---|
Schematic Reference: Wiper/Washer Schematics Connector End View Reference: Wiper/Washer Connector End Views | |||
1 | Did you perform the Wiper/Washer System Diagnostic System Check? | Go to Step 2 | |
Does the scan tool display OFF? | Go to Step 3 | Go to Step 4 | |
Does the headlamp washer switch parameter change state? | Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems | Go to Step 4 | |
Does the scan tool display OFF? | Go to Step 7 | Go to Step 5 | |
5 | Test the signal circuit of the headlamp washer switch for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 10 | Go to Step 6 |
6 | Inspect for poor connections at the harness connector of the body control module (BCM). Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 10 | Go to Step 8 |
7 | Inspect for poor connections at the harness connector of the headlamp washer switch. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 10 | Go to Step 9 |
8 |
Important: Perform the setup procedure for the BCM. Replace the BCM. Refer to Body Control Module Replacement in Body Control System. Did you complete the replacement? | Go to Step 10 | -- |
9 | Replace the headlamp washer switch. Did you complete the replacement? | Go to Step 10 | -- |
10 |
Does the DTC reset? | Go to Step 2 | System OK |