Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Automatic Light Control
When the light control switch is set at AUTO, the automatic light control system automatically turns on or off the taillights and headlights depending on the brightness around the vehicle.
The automatic light control sensor converts the intensity of the illumination into frequency and inputs it to the body ECU. When the light control switch is set at AUTO, the signal is input to connector B6 terminal No. 4 (A) of the body ECU. See WIRING DIAGRAMS . Through communication control of the body ECU and door ECU etc., the taillights and headlights are automatically turned on or off.
- Turn On Function - When the body ECU receives a frequency signal from the automatic light control sensor, and determines that the brightness around the vehicle is below a predetermined level, it controls the connector B8 terminal No. 7 (TRLY) and connector B5 terminal No. 12 (HRLY) of the body ECU. See WIRING DIAGRAMS . This turns on the taillight relay and HEAD LAMP relay, and thus turns on the headlights and taillights.
- Turn Off Function - When the body ECU receives a frequency signal from the automatic light control sensor, and determines that the brightness around the vehicle is above a predetermined level, it controls the connector B8 terminal No. 7 (TRLY) and connector B5 terminal No. 12 (HRLY) of the body ECU. See WIRING DIAGRAMS . This turns off the taillight relay and HEAD LAMP relay, and thus turns off the headlights and taillights. In addition, the headlights and taillights will be turned off when the ignition switch is turned from on to off and the driver door is opened, during automatic light control.
NO RELATED
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.