Wiring frustration

[SyCK]

71' 510, it never had the reverse lights hooked up and someone must have cut the wires to the tranny off the harness somewhere because I can't find them coming into the engine bay. So I decided to wire them straight to a toggle switch, flip switch on they light up and flip switch off an they turn off. Fkn basic wiring, switch gets power and ground then the ACC prong runs to the lights. I ran a test wire back there and wired it directly to one side's wire that I cut before it went into the little harness plug in the back, basically wired straight into the bulb socket. I test it and it works so I'm happy. Now I wired it permanent running the wire over to the passenger side splicing in just the same and ran the wire up to the front along the factory harness. Now when I flip the switch neither work and the fkn thing under the radio sounds like it powers on, I'm guessing something to do with the air conditioner or something. WTF, why would it do that??? The wire runs friggin straight to the rear is is wired directly into the red w/ black striped wires coming directly off the bulb socket. This makes no sense and I am so pissed after having run the the wire back there along the harness (took awhile) and now it's not working.

 

Anyone have any idea why it's doing this?? Why when I wired one side that side worked and now that I wired both inline they don't and that unit under the dash powers on??

[sssr20det510]

check your ground

[SyCK]

check your ground

 

Ground is solid, I ground it in 2 different locations just to make sure and no go :( I just don't understand since it is wired DIRECTLY to the damn bulbs.

[datzenmike]

Now I wired it permanent running the wire over to the passenger side splicing in just the same and ran the wire up to the front along the factory harness.

 

Anyone have any idea why it's doing this?? Why when I wired one side that side worked and now that I wired both inline they don't and that unit under the dash powers on??

 

If you spliced it in, power is now on the wire comming back from the tail light and into the car on the old wire. This may have had a melt down in the past and is touching something under the dash and turning it on.

 

Go back to your last splice and cut the stock wire and leaving leaving yours.

 

 

The new wire you installed could also run into and out of the tranny switch so you don't have to work an annoying switch on the dash. (and forgetting it and leaving on)

[SyCK]

It's something to do with the passenger side reverse bulb since when I unplugged it from the acc wire the drivers side works again. Man I hate wiring gremlins with a passion :angry: Thanks for the suggestions, I'm going to see what's up with the passenger sides wiring.

[Figbuck]

I know wiring frustration. This may seem stupid but did you check for continuity through the new wire(s).

 

One time I wired a rather complicated remodel project with lots of lights and two three and four way switches working different combinations of indoor and outdoor lights. The guy that taught me the electrical trade always "rang out" each circuit before the drywall went up. He had a 24v doorbell transformer and doorbell he clipped to each set of wires and hit a switch so he could hear the bell in another room or location.

 

I got in a hurry and interrupted in the middle of my testing, never got back to it and hung, taped and painted the drywall. When I went to install the switches and fixtures, one of the four way circuits only half worked. I was so bummed out, I thought I didn't run enough conductors for the "travelers"... but I was so positive that I thought the whole thing out and made a pretty good schematic to follow when I laid everything out and mounted boxes and pulled Romex.

 

I wasted almost two whole days trying different combinations of wires to the switches... I looked like everything was done right and some of the conductors I had tagged in big boxes that were full of wires... it all looked right. In the end, I finally decided to ring each individual conductor out. Low and behold two different segments of wire in two different circuits had no continuity.

 

I ended up tearing all the dry wall off so I could replace the Romex. I had used a brand new 500ft roll of Romex that was defective. I rang the whole roll out and there were other spots that had no continuity too.

 

I guess the moral of the story is, when trouble shooting, never assume that any part of the system works. Check the most simple stuff.

[darin620]

I like the idea of wireing thru you Tranny switch. Are you really going to flip a taggle switch on and off every time you back up? that would be a pain.

[SyCK]

I know wiring frustration. This may seem stupid but did you check for continuity through the new wire(s).

 

One time I wired a rather complicated remodel project with lots of lights and two three and four way switches working different combinations of indoor and outdoor lights. The guy that taught me the electrical trade always "rang out" each circuit before the drywall went up. He had a 24v doorbell transformer and doorbell he clipped to each set of wires and hit a switch so he could hear the bell in another room or location.

 

I got in a hurry and interrupted in the middle of my testing, never got back to it and hung, taped and painted the drywall. When I went to install the switches and fixtures, one of the four way circuits only half worked. I was so bummed out, I thought I didn't run enough conductors for the "travelers"... but I was so positive that I thought the whole thing out and made a pretty good schematic to follow when I laid everything out and mounted boxes and pulled Romex.

 

I wasted almost two whole days trying different combinations of wires to the switches... I looked like everything was done right and some of the conductors I had tagged in big boxes that were full of wires... it all looked right. In the end, I finally decided to ring each individual conductor out. Low and behold two different segments of wire in two different circuits had no continuity.

 

I ended up tearing all the dry wall off so I could replace the Romex. I had used a brand new 500ft roll of Romex that was defective. I rang the whole roll out and there were other spots that had no continuity too.

 

I guess the moral of the story is, when trouble shooting, never assume that any part of the system works. Check the most simple stuff.

 

Thanks for that, I'll check the continuity in a bit. Man I bet that sucked to tear the drywall back down lol

 

I like the idea of wireing thru you Tranny switch. Are you really going to flip a taggle switch on and off every time you back up? that would be a pain.

 

Ehh, just when I need to if someone is behind me otherwise I don't give a shit. It's in arms reach and lit when armed so it's NBD.

[DanielC]

First step, are the bulbs good? Do not tell me they are new, they just came out of a package, or they worked last week. Test them now.

Is the socket the bulb fits into good? Your car is 40 years old. Sometimes moisture, or condensation get into the bulb socket, and corrodes the contacts, and they no longer make contact.

Does the taillight assembly have a plug on it? There could be some corrosion in the plug.

 

If there is a plug somewhere in the trunk, get two long pieces of wire, and hook the wire up to your battery, and run the wires back to the trunk, and test the tailight reverse lamp.

I do not know exactly how the taillight is grounded. If the ground wire for the tailights goes through the plug the taillights have, you have to make sure it really is grounded. just because it is bolted to the body of the car, does not mean it is grounded.

 

Here is a webpage that will help you with basic electrical trouble shooting.

http://www.vernco.com/Sparks/id606.htm