I did some rust repair on the floor under my backseat. In order to do this, I had to unplug the harness that runs under the back seat. The harness looks like a flat belt with about 7 or 8 wires running through it. Those wires go to the taillights, and fuel sending unit. When I was finished, I reconnected the harness, and have double checked to be sure that it was completely plugged together, and plugged together the correct way (only goes on one way). Ever since reconnecting that harness, the battery goes dead while the car is parked. I have checked the connection, the wires to the fuel sending unit, and each taillight connection. If I unplug the harness, the battery remains charged. So, I am pretty sure it is somewhere in there. I have a spare taillight harness that I could swap out. That is my next plan of attatck if I cannot figure out where the draw is coming from. It's such a simple set of wires. I don't know what the problem could be. Any other suggestions on what I should look at?
Brian, I had the same problem in my 64 starfire. It turned out to be a short in the flat wire itself that was not evident from looking at it. Turns out that after I had handled the flat wire several times the wire broke internally. Does your flat wire seem brittle? I would examine it carefully to see if there is a dead short somewhere. Also look to see if the wire got pinched somewhere. Maybe after moving it around it is now shorting out near the pinch. Just some ideas.
I did bend it forward and out of the way. Thanks. I'll hook up the test light and see if anything changes when I move it around. Did you find an available replacement anywhere, or this the flat wire specific to this car only?
I think the rear sail panel courtesy lamps are also part of that flat harness, as are the rear cigarett lighters (...if you have them). Make sure that the courtesy lamps are not turned on, or one of the lighter wires is not shorting out, as that could drain the battery ? o No:
None of those circuits should be draining your battery as they wont be getting power unless you have something actuated ie...brake pedal pushed to give the brake lights power or the park lights on...ect....one thing that could be doing it would be your trunk light. my 61 Invicta trunk lt wire goes thru the harness that the tail/brake/backup lights go thru and its a good chance yours does to. at night can you see any lights with a slight glow to them? There are a lot of ways to trouble shoot this problem so if you need help please let me know an i would be glad to help you. you can PM me your phone # if you want and I would be glad to help you out. This is exactly what I do for a living only for corp Jets.
on the teambuick site i saw a diagram that shows an orange wire for the trunk light. that seemsd the only one in the harness that is hot with the key off. see if the clip near the light that hold that wire hasnt nicked that wire and caused a drain. i have attached a cropped pic of what i am talking about.
Brian, I did not find a replacement. I ended up positioning the wire under the mat in such a way that it would work. Later sold the car. Not sure if that flat wire was specific to starfire or not.
Thanks. I forgot all about the trunk light. I'll check that out and give an update afterwards. If that's not it, then I will start pulling fuses until I find the problem.
My first thought would be the trunk light but if that is not the culprit you could disconnect the harness and one circuit at a time re-establish each individual connection with a single jumper wire to determine which circuit it is. Time consuming but it will certainly work, Tom Mooney
Update. First a story, and then my findings. The entire reason why I disconected the battery each time was because long ago, my grandpa was doing body work on a VW bug. He had the taillight harness disconnected and laying loosely in the back with the battery still hooked up. In the middle of the night, the car caught fire and burned the garage down. They said the fire started at the back of the VW. Parked next to the garage was a 69 Charger, which also was a victim of the fire. Parked in the garage, next to the VW, was a 70 Cutlass. Also burned to the ground. Behind the VW was an older Honda motorcycle. After the fire, the only thing left of this bike was the camshaft. Parked in front of the garage was my fathers 64 Chevy truck. They were able to move that truck before it caught fire, but it did get hot enough to melt part of the grill. So, now, anytime I do anything that involves unhooking anything electrical on a car, it has become a habit for me to disconnect the battery until everything is put back together. Especially body work. Now, onto what I figured out. I may have been looking at the wrong end of the car. I think my alternator is bad. Before I did the body work and disconected the battery, everything was fine. Can started fine, and ran great. In the morning, I would reconnect the battery, and pull the car out of the garage. I would let it run for a bit before shutting it off. Then, I would disconnect the battery. 12 hours later, I reconnected the battery and put the car back in the garage for the night. Then disconeected the battery again. I followed this procedure for 8 days. After I finished the body work, I reconnected that wire harness I spoke about in the first post. Then I reconnected the battery. The car sat for a few hours before I started it. The start sounded a bit weaker than normal. I didn't think much about it at first. I moved the car out of the garage and shut it back off. An hour later, I started it back up, (another weak start). I let it run for about 10mins before shutting it back off again. 3 hours later, I went to start it again, and it was dead. Engine spun over 2 times very slowly and then that was it. This is why I assumed the taillight harness was killing the battery. This is why I assumed that it was fine when disconnected. When a new problem develops, you look at the last thing you did that could have caused it. I jump started the car off of another battery and drove it home. When I got home, I shut the car off, then promptly started it back up. It started up, so thinking that it was the taillight harness, I disconnected the battery until I had some more time to figure it out and started this thread. I got some more time yesterday. I reconnected the battery cables. Then I hooked up the test light, and could not find an electrical draw. With the test light hooked up, I moved around all of the wires in that harness. Still nothing. Double checked that the test light worked, and was connected good, and wiggled the wires around some more. Still nothing making the light do anything. Not even dimly lit. So, I decided to take it for a quick spin around the block and then try again. The battery was dead. Didn't even have enough juice to turn the engine one full revolution. I jump started it off of my Ranger, and took it around the block again for about 15mins. That should have been plenty enough time to charge the battery. I then brought it home and shut it off. I waited about 45 seconds and went to start the car again. Dead. Half of revolution of the engine and then dead. When I was driving it, I noticed that my headlights and dash lights would get a little brighter at random times in short bursts. Almost like the alternator was trying to charge, and then stopped. I have no clue if the battery guage on the dash works correctly (that is on the to-do list). So, I am thinking that the alternator isn't charging. Which would make sense about my weak starts at the end of the body work. If, the alternator quit sometime before or during the body work, then each day that I started the car to move it in and out of the garage, I was using whatever power was in the battery alone. With no alternator, it wasn't recharging the battery. Eventually, it would run low on power, cause weak starts, and of course die. The battery is about 5 years old, and the alternator was rebuilt about 5 years ago. I now need to test the alternator, but so far, what do you think?
Could be a bad regulator too. The contacts inside can get a build up on them just like a set of points do. Take the cover off and clean them up and see if that does the trick.
On the voltage regulator, there are 4 pins (prongs, pinouts, tabs, cant remember the actual name). I know how to test the alternator by jumping the Power and Field together, but cannot remember which ones are which. Does anybody happen to know if the order is the same for all GM's, because I cannot find a Riviera specific diagram online?
