Tibo

iTrader: (15)

I wanted to post my recent electrical issue that I was able to solve. Sounds silly to post something that you already found an answer for but when I was searching the threads for members that were in similar situations none of them had posted what solved their problem.

Examples:
https://www.thirdgen.org/forums/elec...s-console.html
https://www.thirdgen.org/forums/elec...me-brakes.html

I connected the brake line that connects from the master cylinder to the rear brake junction on the rear end, bench bled the master cylinder and then bled the calipers. I thought I would press on the brake pedal a couple times (I use the Motive products Power Bleeders so I don't have to push on the brake pedal until it's time to check them) to see if it was firm or easily went to the floor. When I pressed the brake pedal the front parking lights, front turn signals, Gauge cluster lights, center console light and the audible key alarm all turned on. Let off the brakes and they all turned off.

I knew it was most likely a ground issue but I then thought almost instantly that they didn't share the same ground. I looked into and sure enough, they don't. Never the less I began cleaning, checking every ground for continuity and tightening them all down. Still no change. So now I was thinking that I must have cut out some major ground wire when I was rewiring the interior wiring harness. Luckily I still have the dash mostly apart so I could easily look for loose or cut wires. No dice.

I keep the battery on a maintainer so a low charge wasn't the issue and all my grounds have registered at the same voltage as the battery.

Then I noticed that when I pressed the brake pedal the rear tailights did not light up and when I turned on the Hazards all the interior lights flashed. By this time it's 1:30 in the morning and I think that I'm probably tired and am missing something super obvious...

Went out the next morning and went over all the wires in the trunk and found one little 18 gauge ground wire not hooked up. I never hooked it up because I thought it was for the trunk's power lid pull down motor which I haven't put in yet. It's the little 18 gauge solid black wire that grounds right next to the pull down motor. I hooked the wire to the car and instantly all the lights on the car are working properly.

I looked over some more electrical wiring diagrams and it turns out that while those circuits don't share a common ground they do share a common power wire. I didn't know it was possible but now I do--when energized, certain circuits can actually "feed back" voltage/current through their "hot" or "positive" side to other circuits. So a loose or unconnected ground can cause "ghost or gremlin" problems, where certain circuits are energized even though the switches or actuators normally used to "close" them are "open".

I hope this helps someone when searching in the future.

Coz2122

Where is this wire located?

QwkTrip

iTrader: (22)

Yeah when I was building my car that same lighting circuit gave me fits. I was doing resistance checks and in the act of doing so I created alternate circuits. It confused me until I referred to the wiring diagrams, just like you.

Matt Dunn

Hello, im fairly new to the boards. Im wondering how to post a thread addressing a problem of my own. can someone message me and help a third genner out?

Tibo

iTrader: (15)

I described it in the initial post. It's an 18 gauge solid black wire that mounts/grounds to the interior side of the rear bumper area in the well. It grounds just a couple inches from the hatch pull down unit. If you remove that large interior panel from the well you should see the wire there.

henryd3

iTrader: (128)

Go to whichever board your problem falls under. At the upper left corner there is a red, white, and blue rectangular panel that says new thread. Click on it and ask away. Have fun!