Diesel Data: Automotive Repair

Headlight Signal Circuit








HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM (for Manual Air Conditioning System): Headlight Signal Circuit

Headlight Signal Circuit

DESCRIPTION

The A/C amplifier receives headlight operational signals to determine the electrical load. The electrical load signals are used for controlling the number of the PTC heater elements to be heated.

WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. INSPECT HEADLIGHT ASSEMBLY
(a) Check if the headlights come on when the light control switch is turned to the HEAD position.
OK:
The headlights come on.
NG -- GO TO LIGHTING SYSTEM
OK -- Continue to next step.
2. CHECK HARNESS AND CONNECTOR (HEADLIGHT SIGNAL)




(a) Disconnect the connector from the A/C amplifier.
(b) Measure the voltage according to the value(s) in the table below.
Standard Voltage:






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE