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Auto-On Headlight System Symptom Diagnosis (If Equipped)

WARNING: This page is about a different car, the 2008 Suzuki Grand Vitara and 2007 Suzuki Grand Vitara. However, it is still accessible from the selected car via links, so may be relevant.

NOTE:

Use of SUZUKI scan tool makes it easy to check whether a faulty condition is on the input side or output side of BCM. For checking procedure, refer to DIAGNOSIS USING OUTPUT TEST FUNCTION OF SUZUKI SCAN TOOL under Scan Tool Data.
Check each part in the order from the top of the following list.

AUTO-ON HEADLIGHT SYSTEM SYMPTOM DIAGNOSIS TABLE

Condition	Possible Cause	Action
Headlights are not turned ON or OFF automatically even after darkened or lightened	Circuit fuse blown	Replace fuse and check for short circuit .
	Parking brake switch faulty	Check parking brake switch referring to PARKING BRAKE SWITCH INSPECTION .
	Lighting or dimmer switch faulty	Check lighting and dimmer switch referring to HEADLIGHT SWITCH (IN LIGHTING SWITCH) INSPECTION .
	Auto-on headlight sensor faulty	Check auto-on headlight sensor referring to AUTO-ON HEADLIGHT SENSOR INSPECTION (IF EQUIPPED) .
	Wiring or ground faulty	Repair circuit .
	BCM faulty	Check BCM for function referring to INSPECTION OF BCM AND ITS CIRCUITS .