Silver79

Mark, does this have the light control module mounted above the fuse panel? I know the earlier years did. Might want to check that out if it has it.

mark kibort

i didnt see one. what does it look like? dont see any unused connections back there.

Silver79

http://cgi.ebay.com/ebaymotors/Porsc...Q5fAccessories. It looks like this. It says 78-83 but maybe the later cars use it too.

mark kibort

I think you might be on to something here. where is it normally located?

mark kibort

Does anyone know if I am missing (or where mine is located) one of these before I start to dig into the wiring for the brake lights? And, is this only required to run the headlights? I wouldnt think the brake lights or parking lights would run through this.
And, Im wondering if the lights are not working, why the warning lights on the instrument cluster are not illuminating.

Silver79

Poke around in the fuse panel area. It is in there on my 82 but not sure if the later cars have one or where it is located. I had one with a bad board and the left tail light would work and sometimes it wouldn't. By twisting the board you could make the light go on or off. Let me go check on my 87.

Silver79

Just looked in my 87 fuse box. I did not see the module in there. Perhaps somebody else knows how the system works. Joe

mark kibort

anderson says they all have them, so that could be the issue. They are different after '83 or so as well.
maybe thats the issue, BUT, it seems like it is only for the headlights based on the modules markings of wattage. does it have anything to do with the brake light operation?

thanks,

mk

mark kibort

Does anyone know if the '87 version of the "bulb controller" as shown in the picture above, has more pins on it than the early model? the wiring diagrams show it to have 14 connectors, while the one in the picture only shows 12.
I found a connector that is female and looks to be this terminal, with matching wire colors, and it has 14 female pins. the cable/harness it attaches to looks to heads to a wiring harness that ends up toward the rear of the car.

anyone know about this "bulb controller" since i have NO light warnings on the dash, and no brake lights, but turnsignals, im thinking its got to be something like a missing controller, expecially, since I cant find anything like it in the fuse box area.

EDIT: I think , from the drawings, that the 83 bulb controller has 12 connections while the S4 bulb controller has the 14 . I assume the newer controller will have the two additional connections.

thanks,

mk

Aspkiller

I believe the bulb control unit should be located on, at, above or below the passenger parcel tray (those are Porsche's words, ie. Glove Box.

Aspkiller

I don't see where the MY of your car is listed. I presume it's an 87. If you're using a Wiring Diagram for an 87, it may not show locations of components. The 88 diagram that I have, as well as the 91 and 93 diagrams, all show the bulb controller at the passenger parcel tray.

mark kibort

the wired bundle then heads toward the rear of the car. If so, Ive found the connector and the controller is missing. yes, its an 88.

thanks
Mk

86'928S MeteorGrey

I'd assume the newer cars had the addtional 2 pins for the added 3rd brakelight? I recall this module on my older cars, but have not come accross it on the S4 (that I remember)

sendarius

As far as I can discover:

1. The brake lights AND the "Brake light failure" warning light are BOTH powered from this "Bulb Controller". No controller => no brake lights AND no warning.
2. The controller lives at the right side of the passenger parcel shelf (in LHD models).
3. There are different revisions of the controller to account for the third brake light - which does not have additional connectors at the controller, but instead seems to be powered from one of the existing brake light circuits. The difference between versions seems to be in the value of the internal load-sensing resistors.
4. It is common to remove the pin on the connector that sends the "brake light failure" warning to the central warning controller - my '88 S4 has this pin removed, possibly due to the fitment of a third brake light without changing out the controller for the correct version. When I reconnected the pin, I got a warning - when I removed the bulb in the third brake light, no warning.

Xlot may be able to add more - he was investigating adding a third brake light ot his '89 IIRC.

mark kibort

I finally got the ABS working, and tried it out down the street. got the abs to engage, and with hands free on the steering wheel, the car tracks straight. it also locks up the fronts without it, equal, so i think the brakes are working. Ill know more later when we get the lines clear. pedal still goes to near the floor, but the brakes work and rotors get hot, all the way around.

I still have to deal with the clicking noise, from the flywheel hitting the lower bell housing. It only happens at tempurature. Im hoping I dont have a bent flywheel or a bent nose of the rear of the crank. Ill have to pull off the lower bell and see what is hitting and if it is due to flywheel runnout.

last, before we start the gutting process, we have to get the tach working. any ideas where to look with that? maybe the bulb controller will complete the circuit.

really worried about the possiblity of the crank and flywheel being out of wack. think its possible from the impact. i guess Ill find out when I put the indicator on it.

mk