Preparation For Testing

Automatic headlight dimmer is a transistorized system and needs no warm-up. Place car in a well-lighted area, and adjust dimmer range control to approximate center of its rotation. Operate engine at fast idle to maintain constant voltage.

Fig 1: Automatic Headlight Dimmer Switch Terminal ID (Continental, Cougar & Thunderbird)

Courtesy of FORD MOTOR CO.

Fig 2: Automatic Headlight Dimmer Switch Terminal ID (Mark VII)

Courtesy of FORD MOTOR CO.