1994 Mustang

Section 17-02: Lighting, Interior

1994 Mustang Workshop Manual

DIAGNOSIS AND TESTING

Component Test—Courtesy Lamps

Headlamp Switch Test

Disconnect headlamp switch wiring harness connector.
Attach ohmmeter to switch terminals.
Cycle headlamp switch (11654) as required to test all functions of terminals under test.
Closed circuit is 5 ohms or less resistance between terminals.

To Test	Connect To Terminals	Cycle Headlamp Switch To These Positions	Good Switch Circuit Will Indicate
Headlamp Circuit	B1 and H	Off Park Head	Open Open Closed
Park Lamp Circuit	B2 and R	Off Park Head	Open Closed Closed
	B1 and B3	Off Park Head	Closed Closed Closed
LCD Illumination Circuit	DN and I	Off Park Head	Open Closed Closed
	DN and IGN	Off Park Head	Closed Open Open
Dome Lamp Circuit	D1 and D2	Switch rotated to full ON detent.	Closed
		Switch rotated to any position out of detent.	Open
Panel Lamp Dimmer Circuit	R and I	Switch rotated from full ON detent to full OFF position.	Ohmmeter will show smoothly increasing resistance.

Replace headlamp switch if any pair of terminals do not test as expected.