DarkknightgGTR

Having an issue with my 2018 GTRs headlights. Lights are set to automatic - they stay on even during the day in bright light (you can see the headlight bulbs on) but no light icon on the dash. Is this normal? Lights dont turn off if I rotate the light switch even at night - they remain on in every setting.

Secondly when i pull the stalk to flash a car with the high beam, nothing happens. There is no flash of light

However if i turn the car off but keep the ignition on (engine not running) the lights/high beam flash when i pull the stalk. Weird

Anu ideas??

W205C43PFL

Sounds like an electrical glitch, I would had thought it is your light sensor malfunctioning (interpreting it as night time while it is day time) but then you mentioned the high beam flash also doesn't work so there might be an electrical gremlin. Hopefully plugging in your scanner it will yield codes?

Try covering your light sensor (middle top of your windshield you will see it) and/or shining a very bright light on it when at night time if it does anything.

DarkknightgGTR

I dont think its the light sensor as the "light icons" come up on the dash as I would expect them to and go off when I would expect them too but the lights stay on

Then when the car is switched on ie ignition switched on (engine off) - the lights don't respond to the light switch, and then after a certain amount of time, one headlight will go off, and the other stays on..and then vise versa

So definitely an electrical gremlin. Do you think it could be the headlight control unit? Anyone have any idea about this part?

W205C43PFL

I see, and I assume you plugged in a scanner and there are no codes? I wonder if pulling the starter battery and leaving it unplugged for a few minutes then plugging it back in will help reset things?

The headlight control unit, don't usually fail unless water gets leaked in due to a faulty seal but defects do occur... however, never heard of it for your model though so not common if it did.

DarkknightgGTR

No fault code. I need to try at the dealership

I had my steering wheel changed which involved the battery being unplugged but I could try unplugging the battery again.

it's very weird that it all functions normally for a few minutes when I turn off the engine, but then starts playing up again

W205C43PFL

I guess because the voltage changes when the engine is on or off. The alternator might have something to do with it but not sure, hopefully your dealership is able to help you figure it out.