Brake Light Check Light Problems

[Joey Link]

My brake light check light is illiuminated on my check panel and has been for a couple weeks. I checked all my brake lights and couldn't find any problems. A couple days ago I realized I didn't notice the lights on the sides of the bumpers and one was out. I went to remove the bulb and the housing was cracked, allowing water in. It was very rusty, to the point that I couldn't clean up the bulb holder or the plug at the end of the harness that plugs into it. I clipped the wires to the harness connector and tested to ensure I was getting power, I was. I then soldered new connectors onto the end of the harness, slipped the connectors back into the plastic connector plug, and plugged it into a new bulb housing. This worked fine and the light works now, but I still get the brake check light. I then noticed the third brake light wasn't working, so I replace it as well. Now all of the lights are working but I still get the error on the check panel.

Where should I go from here? Please do not tell me to remove the bulb, put a piece of black tape over it, ignore it, etc. - I want to fix this problem.

[lordofthewaters]

Check your brake light switch. If it's on it's way out it'll do such things.

[Van Westervelt]

I have been told that if you used some of the US bulbs, they cause that problem due to the metals that the bases are made out of. I swapped mine out and my light still comes on, but as soon as I touch the brakes, it goes out.

[92 mtechnic cabrio]

I have been told that if you used some of the US bulbs, they cause that problem due to the metals that the bases are made out of. I swapped mine out and my light still comes on, but as soon as I touch the brakes, it goes out.

This isn't a problem. The brake lights light comes on when you first start your car to tell you to check your brakes before you start rolling. Another explanation I've read is that the car doesn't know the state of the brake lights until after you've hit the brake pedal, so it can't check until you step on your brakes.

[Van Westervelt]

So I'm golden then :)

[Joey Link]

That's really odd too. Does it happen on both your E30's Curt?

[Van Westervelt]

Yep, I guess its normal! :)

[thamiracle]

It happen to both of my e30's for sure i know that on ym 86 325e and my 318i, i jsut have brokes put on both today light still on before i even get rolling

[Joey Link]

It happen to both of my e30's for sure i know that on ym 86 325e and my 318i, i jsut have brokes put on both today light still on before i even get rolling

Are you talking about the brake light check light or the brake lining light on the dash?

[Joey Link]

Bump :)

[StereoInstaller1]

OK, so here is a definitive answer to this question:

When you start the car, the "Brake Light" indicator in the DIC (the panel overhead) SHOULD come on, then shut off when you apply the brakes for the first time (on that "RUN" cycle).

If anything else happens, you have an issue.

If your "Brake Light" indicator comes on while you are driving, check the following:

1. Connections to the 3rd brake light housing. Clean with CRC or pencil eraser.
2. The third brake bulb. Replace with a brass base bulb ONLY.
3. The connections to the tail light housings, clean again!
4. Replace brake bulbs with brass base only. *Smear a little bit of Vaseline in the socket. I dip the base of the bulb in the jar because it is easy.
5. The brake circuit ballast resistors, located under the trunk liner on the left rear quarter panel, near the factory amp (if you have one) and the antenna. Small white box with 2 connectors. Dissasemble, clean with CRC, re-assemble.
6. Brake switch, located in dashboard, on the (go ahead, guess) brake pedal assembly. If you are having the "ghost failure" issue, replace the bulbs first, then the switch...even if the bulbs are working fine.

No other bulb in the car has any effect on this circuit.

*I recommend using Vaseline on all bulbs (except headlights) on the outside of your car, on all cars, forever. It damps vibrations, it makes things waterproof. Safe and cheap, rock it forever.

Luke

[Joey Link]

Awesome Luke, I really appreciate it. My issue is when I first start the car it comes on and stays on. I bet it has to do with the 'brake circuit ballast resistors you spoke of. Some water got in there and I bet it fell right on that box. I'll check that as soon as I get a chance.

[Beej '86 325es]

2. The third brake bulb. Replace with a brass base bulb ONLY.
4. Replace brake bulbs with brass base only. *Smear a little bit of Vaseline in the socket. I dip the base of the bulb in the jar because it is easy.

Brass? Aren't these supposed to use the silver base bulbs? (nickel plated I think) That's what all of the manuals have pointed me towards in using. If I remember correctly, the check unit doesn't check for whether a bulb is out or not, but rather a voltage or current. If the circuit is not operating at rate it's supposed to (encountering resistance in the circuit), it will trigger the check light.

I fought this battle for years Your broken bulb in the bumper is not part of the circuit, so that won't affect the check light. I had replaced all of the bulbs with the silver base ones, replaced the switch at the pedal and still had problems. Then I did a retrofit using the later E30 center brakelight and shelf, and that fixed it. It must have been something in the 3rd brake light connection. I haven't had an issue since.

[killa325i]

I have been told that if you used some of the US bulbs, they cause that problem due to the metals that the bases are made out of. I swapped mine out and my light still comes on, but as soon as I touch the brakes, it goes out.

x2