So I asked this question in my Engine Swap thread, and it wasn't a big hit. So I thought it might be a little more accepted here. Most of the electronics are working without issue, as are the headlights and I believe the dash lights, but the tail lights are not working when the brakes are depressed or the headlights are on. I guess what I'm wondering is what all is contained in the "circuit" for the tail lights. So I kinda have an idea what could be malfunctioning.

I'm not very familiar with electrical components. They scare me. haha. Of course, if you happen to know what's wrong, I'll accept that too. haha.

Thank You.

 

There's a lot of things that can cause what you are seeing. The most likely cause however is that the rear harness is disconnected in the trunk. Pull the rear interior plastic panel and the one on the left side. You should be able to see the plug that connects the tail light harness to the wiring harness that runs back from the front of the car. Make sure its connected securely and there is no dirt/grease/grime/etc in the connection. While you have the rear panel out, remove the taillights and make sure the bulbs are ok.

Do your reverse lights or turn signals work?

 

I haven't had an opportunity to get it in reverse becuase the shifter linkage is broken, I'm waiting on it to get home to fix it. But I know the blinkers are working in the front at the very least. I can't remember if they were working in the back when we tested it. I'd imagine not. Is there anything to do with these lights that ran through the engine bay?? I can't imagine why that plug would have been disconnected. We were never back there. The closest to it we were was when we took out the gas tank. I guess it could have naturally come loose and its a coincedence that it's when we swap engines. Were the lights controlled in any way by the computer?

 

Do the front parking lights work?

There is nothing in the engine bay that controls the rear lights. Did you swap transmissions as well as engines, like from auto to manual or vice versa?

The ECM does nothing to control the lights.

Did the turn signals blink normally, or did they blink real fast?

Dropping the gas tank should get you nowhere near the taillight harness.

 

No, we didn't swap transmissions.

Let's assume the front parking lights didn't work. What would that mean? The turn signals were normal. I should have the car back Monday or Tuesday so I can verify what I'm telling you and test out your suggestions.

And yah, I was saying we really went nowhere near it. The gas tank was as close as it got. Haha.

 

The front parking lights and rear tail lights are powered by the same brown wire coming from the light switch. If the fronts aren't working then I would start by verifying the headlight switch is ok. Check for voltage on the brown wire when the switch is on.

It could also mean you have a blown fuse. Check the Tail fuse in the fuse panel under the driver's side dash. While there, check the Stop fuse as well to check the brake lights.

If the fronts are working then we know the switch and fuse are ok. It has to be something in the wiring to the rear lights only. I would start by checking for voltage on the brown wire in the back at the tail lights. Test at one of the light sockets on the left(driver's) side in the rear. If you have no voltage there, then the problem is somewhere in the harness that runs back along the driver's side floorboard.

You could also simply have a bad ground in the taillight harness at the rear of the car. It could have easily corroded over the years and broken off. If you have no reverse lights, I would check this first.

 

Try cleaning out the corrosion in the light bulb sockets, and for the brake lights there are two white switches above the brake pedal.

 

It's home!! Pardon the excitement, I haven't seen it for a month and hasn't really run in 4. haha.

I'd start on helping y'all help me, but it's my mom's birthday and we're going out to do all the fun birthday stuff. haha. But I'll get on it ASAP.

 

Ok I can tell you all the lights are working (can't confirm the reverse lights for aforementioned reasons). All turn signals, head lights, high beams, parking lights, and license plate lights are working correctly. It's just the brake lights aren't coming on when they are depressed.

 

First thing I would check the fuse at the fuse panel marked "stop". If thats ok, I would proceed to the switch above the brake pedal. If you get voltage there, then I would test the sockets themselves at the tail lights.

 

I feel like such an idiot...

There wasn't even a fuse in stop/hazard spot in the fuse box. We must've taken it out for our gauges and didnt know what it was. haha. I put one in and all lights are working correctly.

Thank y'all for your help.