1. When the light switch is in the AUTO position the illumination sensors in the auto light sensor (installed in the windshield) detect the illumination level above and in front of the vehicle.
2. If the upward or forward illumination sensors detect approx. 2000 lux or less in front of and above the vehicle, a headlight illumination control signal is sent to the PJB.
3. The microcomputer in the PJB receives the control signal and sends currents (1) and (2) to transistors A and B respectively, causing the transistors to turn on.
4. When transistors A and B turn on, the headlight LO and TNS relays also turn on. At the same time, the headlights (low-beam) and TNS illuminate.
1. When the light switch is in the AUTO position the illumination level sensors in the auto light sensor (installed in the windshield) detect the illumination level above and in front of the vehicle.
2. If the upward and forward illumination level sensor detect approx. 4000 lux or more for 1.5-2.5 s in front of and above the vehicle, a headlight off control signal is sent to the PJB.
3. The microcomputer in the PJB receives the control signal and turns off the currents to transistors A and B, causing the headlight (low-beam) and TNS relays to also turn off.
4. When the headlight LO and TNS relays turn off, the headlights (low-beam) and TNS also turn off.
