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After_Thought · Joined: 08 Oct 2019 Posts: 44 Location: Hudson ohio

I'm sure this question has been asked 100 times but I've only found one.

Finally got my 924 running and driving but the brake lights don't work. Turn signal/Hazzards work. Tail lights work. Reverse light doesn't (I don't care about that right now).

Replaced #6 fuse and nothing. My front headlights work. (I know there on the same fuse)

Checked the brake switch with a circuit tester and that seems to be working. Put the circuit tester on the out side of the switch and it seems to be getting power and completes the circute when brake is pressed.

What should my next step be? (Never worked on electronics like this) Ive replaced all of the bulbs and don't know what to do next. Any suggestions would be amazing. Thank you

924RACR · Posted: Sun Mar 29, 2020 9:58 pm Post subject:

Well, the grounds are often the problem but since they're shared between the brake, tail etc lights, and since your taillights work, that's not likely the problem.

Assuming you've ensured there's no corrosion in the bulb sockets.

So it would appear that you have a break in the brake (sorry, couldn't help myself!) light wiring between the switch and the bulbs; time to trace the wire and look for the break (again, I know)... or disconnect.

The wire runs past the driver's door under the carpet; if you pull back the trim on the sill etc you can start to get to it. A multimeter would be best for diagnosis; make a small jumper wire to short the BLS (brake light switch, in the industry abbreviation) to have it constantly energized, then start at the bulb and work your way forward until you see 12V. Then head back to the bulb socket, find the break/corrosion etc.
_________________
Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype

After_Thought · Joined: 08 Oct 2019 Posts: 44 Location: Hudson ohio

Fixed it!!. there was corrosion where the bulb met the pannel.

had all of the lights working put it all back on the car then all of a sudden the tail lights didnt work. brakes lights still worked and turnsignal.

when i took it apart i released i switches the turn signal bulb with the tail light bulb. could that have shorted something?

924RACR · Posted: Mon Mar 30, 2020 10:07 pm Post subject:

Do you mean you switched the bulbs? No, that shouldn't have shorted anything. Sounds like more corrosion, perhaps it's time to remove the metal backing plate all the bulbs plug into and clean with metal polish to remove the rest of the corrosion?
_________________
Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype