2001 C4

I noticed that 4 of the 16 LEDs in the body 3rd brake light were out. I removed the whole thing and ordered a replacement.

Raised the spoiler so I could still have a 3rd brake light.

Decided I did not want to drive around with the spoiler up so I pulled the light from the spoiler and installed it in the body....... it doesn't work.

Put it back in the spoiler and it works fine.

Put the original body light back in the body and now none of the 16 LEDs work at all.

All of the rear tail/brake lights work except the 3rd brake light in the body.

Hooked up a test light and the female plug for the body 3rd BL has no juice.

No idea where I screwed the pooch on this one.

Looks like under the hood is a long black plastic cover with four fasteners.

Do those just pull out or do they unscrew?

Can that plastic cover be removed without taking the entire intake off? (Looks like a very snug fit.)

Where does the wiring for the body 3rd brake light run to? Maybe I can test it there before I start pulling too many panels.

Should have been such a simple fix.

Thanks in Advance.

 

OK how about this? Can anyone answer this part for me?

Looks like under the hood is a long black plastic cover with four fasteners.

Do those just pull out or do they unscrew?

Thank you

 

Ha. HA! HAHAHA!!! I figured it out!

So it appears that when the wing is up, the power to the body third brake light is cut off. When the wing is down the power is restored to the body light and cut off from the wing light.

I was doing all my testing with the wing up.

So now as soon as my new brake light arrives they will both be working.

Hope this helps someone else in the future.

 

Well I'll be dang. Who woulda thunk it. Well obviously the sneaky German Engineers. I woulda spent some time running in circles with this too as I never see the back of the car with wing deployed and brake lights on etc.

Thanks.

 

This has happened to other members, probably many times.

 

If your 3rd brake lights are LEDs, there is a good chance the polarity on the connector on the tail is wired opposite of the normal (non tailed) 3rd brake light.
I changed my bulbs to LEDs and I recall having to install the "tailed" 3rd brake lights just opposite from the normal 3rd brake light...

 

Why didn't you order the replacement prior to removing the 93% functional one and embarking on this strange and fantastic trip?

I believe OP may have omitted this critical first step:
"Loaded 150mg of meth into my pipe. Smoked it."

 

Well, those 3rd brake lights are not LEDs. They are small bulbs. You can pry the housing open slowly and replace all the bulbs. I forgot what type of bulbs they are but I got my replacement bulbs from o'reilly. They are common bulbs type and I think they are 8 bulbs in that 3rd brake light housing.

 

And we have my first ignored member. 😀

 

I figured your first ignored member was in your trous...eh, never mind.

Happy tweeking!