j.kenzie@sbcglobal.net

Hi guys,
i ordered a superbrite LED brake light bulb set for my 84. What is the simplest way to defeat the bulb warning? I don't mind cutting a wire. I'd rather not pull the pod. I'd rather not open up sealed components, but will if needed.
Thanks,
Dave

MainePorsche

Dave,
On your MY 84 I believe it will be pulling male pins 9 & 12 out of the Bulb Controller harness at the Bulb Controller attachment to disable brake light control. No cutting.

Add: WD image

MainePorsche

Dave,
The above is incorrect.
Wait for update.
Sorry.

MainePorsche

Correction:
Pull male pin 1 at the Bulb Control harness connection.
Pins 9 & 12 are power out of Controller to bulbs.

Ed Scherer's description of Bulb Control harness/pin disabling in an S4:

https://rennlist.com/forums/928-foru...ml#post3951223

Eplebnista

And here is the guide applicable to the 928's that have the recessed tail lights that God intended them to have:

https://rennlist.com/forums/928-foru...ol-module.html

davek9

You really don't need to pull the pins if you just jump them all (stop and Tail) at the connector.
That is unless you are not doing all the tail lights and still want to use the Lamp Controller for the others.

Dave K

j.kenzie@sbcglobal.net

Ok, I installed my LED brake light bulbs. I get the stop light warning. Expected.
I plan to drop my PS package shelf with the bulb controller attached to it. So far I have only changed the brake lights and head lights to LED, so I need the bulb controller to run everything else. I think I can find the brake light input signal in the controller harness, and I think I can find the brake light output leads, #'s 9 and 12 I think. Should I put parallel jumpers, then re-connect the controller. Should I cut or remover pins, then jumper. I still need to be able to cancel the startup stop lamp warning. I don't want to use load resistors, because the LED's are there to reduce electrical load.
Sorry to ask again, but I'd like to confirm your ideas.
Thanks again,
Dave

j.kenzie@sbcglobal.net

Thanks for your patience guys. I found an old thread:
https://rennlist.com/forums/928-foru...ol-module.html
It described removing the #2 pin from the harness connector. That was an 85, and it looked about the same as my 84. Anyway, that worked. No warning light, and all rear lights function fine.
Thanks again,
Dave

MainePorsche

Wow, Pin 2.
I went through the WD and pins 1 & 2 come off the brake light switch at pedal. I traced their courses and thought pin 2 disconnection would disable lights.
Sorry for the mis-info.
Glad you got it where you want it.
Craig

j.kenzie@sbcglobal.net

Craig, no problem. Thanks for all your help. The WD's are weak on those connections and the little diagram on the ECU itself is almost impossible for me to read. I went by the old post, to see if I would get lucky, and it worked.
Thanks,
Dave

MainePorsche

Dave,
Thanks for understanding. I just try to help.
I feel the same as you about energy conservation. The bulbs that I've used were plug n play. No resistors. The only complicating variable was the turn signals. They would either require resistors or a new turn signal relay able to cycle/function with such low current. Ed Scherer used this in his comprehensive thread, and I went the same route - https://www.superbrightleds.com/moreinfo/782/.

j.kenzie@sbcglobal.net

Yeah, Craig. Regarding energy conservation, I targeted the headlights because they are high output, and the brake lights because they are pretty high output, but often used while at idle. I foolishly forgot about my third brake light which is the same bulb, so I ordered another LED unit. The difference in my car's voltage now at idle, with a/c running, all lights on is remarkable. This is the LED I have been using:

https://www.superbrightleds.com/more...ofit-car/1326/

Dave

MainePorsche

I have my headlight LEDs still in box - I'm doing contract work away from home and car so can't do yet - I already have the car in winter sleep mode.
Be careful with putting LED in third brake light - it will cause absolute problems with your cruise control - the control unit needs the ground that the filaments of incandescents provide. I'm LED'd all except 3rd brake light. Ed Scherer's thread will confirm this too.

Hilton

Win!

I was going to add this, but your way sounds easier

Defeating the Bulb Control Module
https://rennlist.com/forums/928-foru...ol-module.html

In pdf form with the pics which are now missing:
https://drive.google.com/file/d/0Bzv...ew?usp=sharing

Next question - does your cruise control stil work?

j.kenzie@sbcglobal.net

Thanks for the help. I couldn't find picture of the circuit board mod. BTW, except for verifying its function, I've never used my cruise control.
Dave