DIMMER SWITCH
The flash-to-pass dimmer switch is located in the steering column. One switch position provides low beam operation and the other provides automatic operation. Momentarily placing dimmer switch lever halfway between positions flashes high beams.
HIGH-LOW BEAM RELAY
The high-low beam relay switches the headlight beams. It is controlled by the dimmer switch or by the sensor-amplifier.
DIMMER RANGE CONTROL
The dimmer range control adjusts system sensitivity to surrounding light. Rotating the control toward maximum ON position increases sensitivity; headlights dim when approaching vehicles are at a greater distance. Setting control to OFF position permits manual operation of headlight beam with column dimmer switch.
SENSOR-AMPLIFIER
The sensor-amplifier senses light from oncoming headlights or from taillights of vehicles ahead. The unit is adjusted for aim and sensitivity at the factory, and is then sealed with epoxy. The epoxy prevents access to factory sensitivity adjustments and interior parts.
Note. If an automatic headlight dimmer malfunction cannot be immediately serviced, manual operation of headlights may be obtained at the dimmer switch by disconnecting sensor-amplifier and turning dimmer range control to the OFF position.
SENSOR-AMPLIFIER HORIZONTAL & VERTICAL AIMING
Sensor-amplifier horizontal and vertical aim is preset at factory and is not adjustable. Horizontal aiming is preset at 2 degrees left.
Autodimmer Indicator Inoperative
Check for burned-out bulb, and replace if necessary. Check for defective switch in potentiometer assembly and defective dimmer switch. To do so, turn headlights on, and set dimmer switch to automatic position. Check for battery voltage at Yellow wire of potentiometer connector. If battery voltage exists, replace potentiometer assembly. If voltage does not exist, check dimmer switch and wiring.
No High Beam With Dimmer Range Control Turned Off
Check for defective high-low beam relay, and replace if necessary. Check dimmer switch for proper operation.
No High Beam When System Is On Automatic
Check for loose connections and poor grounding at sensor-amplifier. Check for defective sensor-amplifier. To do so, move dimmer range control to minimum range without turning it off. Hold a black cloth directly over sensor amplifier lens. Sensor is defective if it does not switch to high beam within a few seconds.
Only High Beam When System Is On Automatic
Check for defective high-low beam relay; replace if necessary. Check for defective sensor-amplifier. To do so, turn headlights on. Ensure sensor is exposed to sufficient light and dimmer switch is in automatic position. Disconnect sensor-amplifier connector. If headlights return to low beam, replace sensor-amplifier.
Headlights Dim Too Soon Or Too Late
Check for loose amplifier or mirror support, and tighten as required. Check for defective potentiometer or sensor-amplifier. See AUTOMATIC HEADLIGHT DIMMER SYSTEM TEST under TESTING. If headlights dim too late, clean windshield and retest.
No Flash-To-Pass
Check for blown fuse or circuit breaker. Replace fuse in position No. 14 if necessary. Check for defective dimmer switch.
No Manual Low Beam
Check for defective high-low beam relay. To do so, remove high-low beam relay, and check for continuity between Red/Yellow wire (circuit No. 15) and Red/Black wire (circuit No. 13). Check for defective dimmer switch. To do so, disconnect dimmer switch. If headlights return to low beam, replace dimmer switch.