3RD brake light wiring question

[ghrays]

I did that too but found that the 3rd light comes on dimly without the pedal being pressed. It comes on fully bright with the pedal. Not a problem IMO, just wasn't expecting it.

When using an LED bulb for the third brake light, soldering the two green/black wires together got rid of the check panel warning light for brake lights. The LED bulb was dimly lit whenever the ignition power was turned on. Twisting on a tiny 6 OHM 0.25W resistor onto the socket terminals solved that issue.

[PDXPeter]

I did that too but found that the 3rd light comes on dimly without the pedal being pressed. It comes on fully bright with the pedal. Not a problem IMO, just wasn't expecting it.

[Bmjpv]

Check panel brake light FIX !!

Thank you for that tip , fixed problem check panel light for brakes that would not go out , thanks !

[Mike36]

1 1/2 year bump. I finally have check free panel! Hallelujah!

[e30rapidic]

8-1/2 year bump for a great fix.

[Mo Brighta]

I have added third brake lights to several cars that came without - some 2002s and early E28s. No check panel monitoring, but no warnings either! It's not that hard to verify all tail light functions -- look in your rear view mirror after backing into a space in front of a store with glass front. Your lights reflect off the store window, you see the reflection. Done.

Your 89 came with 3 brake lights, so why not use the wiring from the stock third brake, getting the benefit of the check panel monitoring?

I would tap the two wires from the circuit board that now go to the stock lamp, extending and connecting them instead to the wing light wires. I like to solder and insulate everything with heat shrink tube, to avoid that nasty smell when power is accidentally grounded ... no, the fuse would blow first.

Are you planning on removing the stock center brake light assembly or leaving it there?

[ModernclassicxF]

Hey I bought a Zender spoiler with third brake light that came off an Ix for my Ix, now unlike the convertibles I'm sure I'm going to have to do more to get this working. Mine is similar as the one mentioned above with a two wired wing. Does anyone have experience adding third light to a car without origional third light? It came off an ix but not sure on how to do it properly and trying to prevent headaches before install.

[T.Dot_E30]

So I jumped the wire OP said. But I was wondering does your guys check brake light still stay on, until you hit the brakes and it goes away?

yes, once you step on the brake the system knows if the brake lights work or not.

Hence the "Check" blinking until you do.

[Kwaaahhh]

So I jumped the wire OP said. But I was wondering does your guys check brake light still stay on, until you hit the brakes and it goes away?

[Kwaaahhh]

Any chance some have some pics of the wiring done? Got a IS trunk painting right now to swap on my vert. :up:

[Garageaholic]

I am going to revive this thread...

I was troubleshooting my brake check light system.. I will try this soon, but I want it to work LIKE IT SHOULD....

With that being said, I inspected the circuit board within the 3rd brakelight housing. There was some corrosion, so i cleaned it off and the check light doesn't go out... I may give up and simply connect the wires, but I figure that I would give it a good college shot..

How would one test this? What is the proper resistance of the bulb that one should use?

[rkettner]

the third brake light can also be the source of water getting into your trunk as i found out.

[DaveSmed]

Glad to hear it helped.

Under the drivers knee bolster, there is an orange box near the ABS computer. It has 4 (IIRC) orange connectors. Unplug them. No more light.

[cactusjacks1]

Ok, so I am glad I checked first. Green/red and brown get the light working and connecting the two green/black bypass the check system for the 3rd light.

BTW, cabrio owners, you might want to pull your trunk lid 3rd brake light and inspect it. I had some serious rust going on an otherwise rust free car.

You have found a real simple fix - I made a jumper wire to connect the 2 & WALA !! brake warning light on the check panel is OUT.

Any hints on the SRS light staying on when you replace the air bag steering wheel with a non air bag one??

Thanks a 1,000,000 !!

Jack

[DaveSmed]

So, if you have completely done away with the third brake light, you jump the 2 wires (keeperjones talks of in post #2) & the "brake light" warning bulb on the "check board" will go out??

Yup.