Fog Light Diagnosis

The fog light lights up when the front-ECU turns ON the fog light relay (inside engine room relay box) according to the fog light light up request signal output from the ETACS-ECU when the fog light switch is turned ON, while the headlight is lit up on low beam. What's more, the lights automatically dim with the headlight automatic shutdown function.

The lights dim with the following operations executed while the fog light is ON. What's more, the lights automatically dim with the headlight automatic shutdown function.

• The fog light turns OFF (dim) when the headlight is switched to high beam. The fog light will turn ON again when the headlights are returned to low beam, at this time.
• The fog light will turn OFF (dim) when the headlight switch is turned OFF (taillight ON or taillight and headlight OFF). The fog light will not light up again though the headlight is returned to low beam, at this time.

The fog lights are controlled by the Simplified Wiring System (SWS). For troubleshooting, refer to SWS DIAGNOSIS .