Hey guys, I've got a wiring/lighting issue I was hoping somone could help with.

Whoever had the car before me, I'm guessing the brake lights went out on him. Whoever tried to fix it for some reason spliced into the power wire leading into the hatch brake light. They then proceeded to run that wire into the brake lights so that they can run lights. The problem that I have is that with the way they did it whenever I press on the brake while the tail-lights are on the light barely gets any brighter. Any ideas on what I should do to fix it? I'm not sure if it makes it to where the brake lights are always on or if it just doesnt get hardly any brighter when I press on the brakes.
Also, whenever the lights are turned off and you press on the brakes, for some reason the dash lights light up.
It's a 96 Z28

Thanks for the time!

 

Sounds like you have a bad ground for the brake lights. Feeding power back into the brake lights still needs a ground to work. Since there isn't one, the power will feed through the tail lights for a ground source which will feed power to the dash lights.

 

Thanks for the advice.
Do you happen to know where the grounds for the brake lights are?
Or where I could figure out where they are?

 

Might check the ground behind the drivers side rear seat area.Somewhere (when you are sitting in the rear seat,drivers side,look left,into the body,going back)It's there hiding.Wish I could be more dicriptous,but it's there.Beer time.My02.Why didn't they just replace the brake light switch?Gone.

 

Lol..trust me i've been wondering half the day what they were thinking about with this wiring set up.

 

If I had my Helms manuals on hand I could help you out. But you might want to just invest in some yourself, that way you have the wiring schematic and you can follow all the circuits yourself. Those things have helped me lots of times.

 

The problem might be more complicated than I originally thought. For some reason whenever the tail lights are on the third brake light is on. That's not suppose to happen is it? Also I think the wrong plugs were in for the brake lights because they were only two wire plugs instead of three wire. I have no idea how to get it fixed.

 

I'll try to help you with this, but I only found the first half of the wiring schematic on shoebox's site.

http://shbox.com/1/exterior_lights.htm

This covers where the circuit is powered up, the fuses, brake light switch, turn signal/hazard switch, third brake light bulbs, and some grounds. It stops short when it comes to the rear brake/turn sockets, but we do have some good info to work with.

First off, I need to know how much do you know about testing electrical circuits? If you don't know anything, that's not a problem, but I do need to know how much detail to include.

You're going to need a test light, and a volt/ohm meter.

 

Lights that light up when they aren't supposed to are only going to happen for two reasons. The first is not very common. It's called a cross short. That's when a wire from one circuit touches and crosses paths onto another circuit and operates it when the first circuit operates. As I said, this is not very common. I've only seen it a handful of times and it has always involved a wet green corroded conector somewhere. The second is what everyone is talking about, a bad or loose ground. Have you ever been behind a car that when they hit the brakes, the reverse lights go on and brake lights go off or really dim? That's a bad ground. Electricity is always going to try to find a path to ground(neg. bat. terminal) and what ever is the easiest path, is what it will take. If the regular path is not there, it will sometimes be able to backfeed it's way through somewhere else and in most cases sort of make that circuit work. So, that's why so many people are talking about a bad or loose ground.

How do you test? Let me know what you know and we'll go from there.

 

If you look closely, you will see that the schematic is continued for the rear lights. It's a 1995 schematic and 96 may be different.

 

Holy cow, I totally misses that the A&B symbols were clickable. That's waht I get for not really reading. Thanks Shoebox. YOu're right, there might be a difference between 95 & 96, but in this case, we gotta use what we can get...

 

Thanks for the help guys. I think I finally figured out what was wrong. The third brake light was hooked up to the tail lights for some reason with a random wire that was spliced into both. Therefore, whenever the tail lights were turned on, the third brake light acted like a tail light as it was drawing power from the tail lights. I also noticed that this wire was hooked up to the blinker bulb which made it act strangely. Also, I believe that the plugs used for the bulbs were the wrong ones, because they only had two wires running off of the plug instead of three. I bought one new plug since that's all the part store had. So i've got the lights working on one side now and hopefully whenever I get another plug it will work on both sides, even though it still wont be wired up the right way. Could someone tell me which lights are suppose to light up when the brake is pressed and which ones are suppose to when the blinker is on?

 

Sounds like when my brother in law hooked up my speakers in series,better get an electical person to hunt this one down.My02.

 

According to the diagram, there are four three wire sockets. Two for each side. All four will light up brakes and both on each side for turn signals.

I'm glad to hear you got it figured out.