I am an auto repair professional. I have come into contact with this question of yours! There are many kinds of faults in car headlights, one of which is that one side of the lamp is bright and the other side is dark! Let me explain it with Toyota VIOS. Toyota VIOS lights have two switches. One is a light switch and the other is a dimmer switch. It can be judged that there is something wrong with the dimmer switch if the width indicator lamp is completely off, and it can be judged that there is something wrong with the dimmer switch if the two sides of the lamp tube are changed continuously and lit at the same time.

One side of the light is not lit (the dimmer switch and the light switch are normal). Since VIOS has no relay, go to the connector behind the lampshade to test, and then check the light bulb if there is no problem.

One side is bright and the other side is dark. The style comes from the lighting insurance of the problematic party. There may be a problem!

The above is my inspection and analysis of automobile lighting failure. Fault vehicle Toyota VIOS.