Headlamp Control Module: Description and Operation

With the Ignition SW turned OFF, current flows to TERMINAL 7 of the Integration Relay Gauge Fuse).
Voltage is applied at always to TERMINAL A-2 of the Integration Relay through the taillight relay (coil side), and to TERMINAL A-3 through the headlight relay (coil side).

1. NORMAL LIGHTING OPERATION
ON>
With light control SW turned to TAIL position, a signal is input into TERMINAL A-1 of the Integration Relay. According to this signal, the current flowing through TERMINAL A-2 of the relay flows to TERMINAL A-1 --> TERMINAL 2 of the light control SW --> TERMINAL 11--> GROUND and taillight relay causes taillight to light up.
ON>
With light control SW turned to HEAD position, a signal is input into TERMINALS A-1 and A-4 of the Integration Relay. According to this signal, the current through TERMINAL A-3 of the relay flows to TERMINAL A-4 --> TERMINAL 13 of the light control SW --> TERMINAL 11 --> GROUND in the headlight circuit, turning headlight relay ON. The taillight circuit is same as above. These cause the Headlights and Taillights to light up.

2. LIGHT AUTO TURN OFF OPERATION
With lights ON and Ignition SW turned OFF (input signal goes to TERMINAL 7 of the relay), when door on driver's side is opened (input signal goes to TERMINAL 6 of the relay), the relay operates and the current is cut OFF which flows from TERMINAL A-2 of the relay to TERMINAL A-1 in taillight circuit and from TERMINAL A-3 to TERMINAL A-4 in headlight circuit. As a result, all lights are turned OFF automatically.