HEADLAMP SWITCH INPUT CIRCUIT HIGH

For a complete wiring diagram Refer to Section 8W


  • When Monitored:

    Ignition on.

  • Set Condition:

    The BCM detects a voltage greater than 4.75 V on the Headlamp Switch Input for more than 5 seconds.


Possible Causes
 
HEADLAMP SWITCH OPEN
 
HEADLAMP SWITCH MUX CIRCUIT OPEN
 
HEADLAMP SWITCH RETURN CIRCUIT OPEN
 
BODY CONTROL MODULE
 




Diagnostic Test

1.INTERMITTENT CONDITION






Does the Scan Tool display: HEADLAMP SWITCH INPUT CKT HIGH?

Yes
  • Go To2


No
  • The condition is not present at this time. Monitor Scan Tool parameters while wiggling the related wire harness. Refer to any Technical Service Bulletins that may apply. Visually inspect the related wiring harness and connector terminals.
  • Perform BODY VERIFICATION TEST - VER 1.

2.HEADLAMP SWITCH OPEN









Does the Scan Tool display Headlamp Switch voltage below 0.5 volts?

Yes
  • Replace the Headlamp Switch.
  • Perform BODY VERIFICATION TEST - VER 1.


No
  • Go To3

3.HEADLAMP SWITCH MUX CIRCUIT OPEN








Is the resistance above 5.0 ohms?

Yes
  • Repair the Headlamp Switch MUX circuit for an open condition.
  • Perform BODY VERIFICATION TEST - VER 1.


No
  • Go To4

4.HEADLAMP SWITCH RETURN CIRCUIT OPEN








Is the resistance above 5.0 ohms?

Yes
  • Repair the Headlamp Switch Return circuit for an open condition.
  • Perform BODY VERIFICATION TEST - VER 1.


No
  • Replace the Body Control Module.
  • Perform BODY VERIFICATION TEST - VER 1.