Rear spoiler LED brake light not working, Wiring hints for making LED work? Options

[ian0]

Hi there,

have owned my 1994 ST202 for nearly 6 years now, and the rear spoiler LED brake light has never worked. I wasn't too bothered, as there are still 5 other brake lights (4 in the tail lights, and the high level one above the number plate, as the car is an import), but I have now decided it deserves to work, as it's sitting there anyway. Does anyone have any hints as to where to look for the wiring, or other things to check to get it working? Also, could it be set up to work as a rear foglight?

Any suggestions welcomed.

[K-ESD]

i'm not too familiar with the SS-I but in general, the wiring for it should be right under the panels on ur hatch. Pop those off and look for wires that are going into the spoiler. Grab a multimeter and test for voltage.
Yes it can be setup as rear foglights, however LEDs won't provide much light for it to be useful. If you want to do it, you can bring a wire from a switch in the front (use the cig power as the source) and track down where the wires pass to get to the LEDs and once you find a nice spot to cut, connect ur switched wire to the wire going towards the rear. This of course, takes a conciderable amount of work and familiarity with car electrical.

[ian0]

Thanks for that! I opened the inspection flap thing, and found one of the wires to the spoiler brake LED had been cut. I just re-connected it, and wahay! the LED started working again. Only problem is that as soon as I hit the brake pedal after starting the car, the rear brake light "bulb out" warning light comes on in the dash, and stays on until I turn off the ignition. It is quite a bright orange light, particularly when you're driving at night, and I am beginning to understand why the previous owner cut the wire! Mind you, as long as I know the lights are actually working, and that the wiring harness isn't going to melt or anything, I can probably live with it. Can't help thinking that a resistor or something might help the situation though. The LED is wired in parallel to the bootlid brake light, rather than in series, so maybe the lower overall resistance of the circuit is triggering the diagnostics?

[K-ESD]

hmmm... thats interesting
if it does work by sensing current, which would decrease if a bulb was poped since there would be one resistor missing from the paralel node. For diagnostics, try getting ur hands on a variable resistor (like a volume knob off an old stereo) and play around with the resistance to determine what is the range of current which activates the light. Also, stick a ohm meter in the LED circuit to see what kind of resistance you get. I'm sure with enough fiddling around you should be able to solve the problem.

This is somewhat a minor problem, i guess you could just pull the bulb out of the cluster since it bugs you. If worst comes to worst, u'll blow a fuse before ur wires start melting.
I'm curious to see how those Japs wired the thing up

EDIT: i'm still thinking about this one... does ur LED lights come on (but dimmer) with the parking lights? If so, you might've connected the parking light wire to the brake light wire on the LED and vis versa. One other way to find the right resistance is to unlug ur LEDs, take the brake light fuse out and stick an ammeter in there (careful not to short), mesure current and calc resistance. Then do the same with the LED light plugged in, compare data, in theory you should have more current going thru it. If you somehow get less current, then you can figure out what resistor you would need to stick in (paralel) there to up the current by a little bit.

This post has been edited by K-ESD: Nov 2, 2005 - 3:31 PM