I am trying to find a short in my 79. I hooked test light in series to neg. battery and test light lit up bright. I started unplugging things under hood. wiper motor starter harness, etc. When I unplugged the starter harness the test light went out. plugged it back light came back on. I then started pulling the wires out of the connector that goes down to the starter. first one was the red wire. light goes off. does that mean the red wire is going to ground? I think that is the wire going to alt.?

thanks

 

ooopppps.... I think the red powers everything..huh. so if I disconnect it I would lose power

 

Hook all that back up, you were on the right track but zigged whn you should have zagged. Pull the fuses 1 at a time, begin with the CTSY fuse. It is usually the culprit with the light timer dieing. Unplug the timer and the short should go away if that is the problem

 

im guessing the burglar alarm ,alot of people had problems with them ,to make things easier,I put a battery disconnect on my 79 !!!

 

Ctsy. Is the winner. Now to find the short

 

Do you mean a true short circuit that causes fuse(s) to blow?

Or do you mean a constant draw of power that drains the battery?

 

Regarding the alarm system:

Presuming that the dedicated anti-theft horn isn't sounding, the only other component of the factory alarm system in a '79 that draws power is the anti-theft relay. It is in the center console ahead of the shifter. You'll see both a relay and a flasher. Remove the relay and if your current draw is eliminated you've found the problem. (Energizing the relay should cause the anti-theft horn to pulse via the anti-theft flasher but the horn might be removed, disconnected or defective.)

 

It takes bout 2 weeks to drain battery. But sometimes while driving you can smell an electrical smell but no fuse are popped

 

Here is a list of what is powered by the CTSY circuit from the factory:

1) The courtesy lights to include glove box light, passenger vanity mirror light and spare tire light
2) The alarm system
3) The power door locks
4) The power antenna
5) The clock
6) The cigar lighter
7) The horns

Here are common places to look for problems in each:

1) Courtesy lights. The electronic timer module is well known for causing a current draw. Remove the glove box and it will be to the right (it is supposed to be taped to the harness). Remove it and see if your draw goes away. You can get normal (not timed) courtesy light function by removing the module and jumping the two white wires on the harness connector. The spare tire light comes on with the rest of the interior courtesy lights. If you've removed them previously but didn't know about the spare tire light its lens could be filthy and the light burning constantly. Neither the glove box lamp nor passenger visor courtesy lamp should cause a draw unless they are burning. There is a connector for the visor (orange and black wire) very near the courtesy light timer module.

2) Alarm system. The alarm relay located in the center console ahead of the shifter. It should not be energized unless the alarm system is set and triggered.

3) Power door locks. Nothing about them should cause a constant drain. Any problem should cause the fuse to blow.

4) Power antenna. A defective "down" limit switch can keep the power antenna motor running constantly (well--it should cut in and out on thermal limit). If this is happening you should hear a noise from the antenna motor. The power antenna relay is energized from the RADIO fuse so that won't be your problem. The easiest place to disconnect the power antenna is from the connector behind the driver side rear speaker.

5) Clock. A properly working clock will draw only a tiny amount of current. I suspect (but do not know for certain) that a defective original type clock could cause a more significant draw if it continually attempting to "wind" itself. Replacement quartz type clocks should be incapable of causing a significant draw. The only way to disconnect is to remove the center console gauge pack.

6) Cigar lighter. Any problem should cause the fuse to blow.

7) Horns. If your horns blow they shouldn't be part of the problem. If they don't (or if "alternate" wiring has been used to get them working), remove your horn relay (in a ridiculous location above and left of the fuse box).

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Since the CTSY circuit has constant power and is easy to find throughout the cabin it is a VERY common place to tap into for aftermarket accessories. Look for any aftermarket type thing connected to an orange wire.

 

re: The electrical smell.

I completely removed the cabin wiring harness from my fully-equipped '79. It is NOT a pretty sight! Frankly I'm surprised that more C3s don't go up in flames due to electrical fires. Seriously--keep a fire extinguisher in one of the rear storage compartments!

1) It looks like the same general harness design was used through many changes of electrical options, location of controls and other components. It seemed to be in GREAT need of a COMPLETE re-engineering.

2) Some of the multi-wire connectors find one of the wires significantly shorter than the rest with it taking ALL of stress with when you are required to move things, disconnect, connect, etc. during normal service.

3) The location and connector design of the horn relay nearly guarantees that the wiring will be greatly stressed when you remove the relay.

4) Both the CTSY circuit and ground are FILLED with factory splices. Splices themselves aren't necessarily bad but these are not very good splices. They use heavy gauge plain steel two-ended splices that while originally mechanically secure oxidize (rust) over time. Oxidation in a splice between dissimilar metals is NEVER a good thing Also the splices are wrapped with a single layer of very thin tape. Worst of all there was at least one location where splices between positive and negative conductors could come in physical contact with one another. EVERY splice in my harness showed signs of overheating. The tape over the splice body was utterly dried out and no longer completely intact. The wire insulation close to some of the splices was also overheated and brittle. I soldered in a 12 gauge copper wire "bridge" across all of the splices and wrapped them with heavy arc proofing tape. (The arc proofing tape was overkill but I had it around...)

 

WHO in hell needs courtesy lights in a VETTE??? you can't see to get in/out of the car, summfin RONG you don't need be driving......YA THINK????