Car is a 1970 BB, no A/C. All new wiring harnesses throughout.

The problem is, with everything hooked up, as soon as I go to connect the battery, the horns start going off. I believe I've checked every possible ground with a multi meter and they were all safely grounded. Two other anomalies with this are 1. the fuel gauge isn't working and 2. the 25 amp fuse for the a/c and TCS blows every time I turn the key (none of the TCS components are hooked up). I disconnected the horns and reattached the battery but started to see a small amount of smoke near the horn relay so I quickly stopped that. I have the assembly manual and don't think there's much room to mess up the connections, especially with new harnesses. I didn't replace the horn relay during the rebuild but am starting to wonder if it's the culprit. Anyway, I'm not very savvy with circuits and the electrical side of things and I've been at this for days now. Any help would be really appreciated!

Chad

 

If you happened to buy a Lectric Limited harness you might need to check the wiring at the connectors. I bought the new harness from them a few years ago (all of the harnesses from the headlight to tail lights) from them and had a number of issues with the wrong placement of wires in it's connectors.

 

As your finding out C3 vettes are electrical nightmares. A lot of things share grounds and rely on resistances from other components ect. check everything. even a blown bulb or something disconnected will cause wacky things to happen. Best of luck

 

Disconnect your turn signal switch connector under the steering column and see if the horns blow. If they don't...and when you go to connect it back up and it blows the horns...your problem is in the horn circuit ion the steering column.

The BLACK wire going to your horn relay is the CONTROL wire from the horn button/steering column...and when the horn button is pressed...this BLACK wire gets GROUNDED....thus causes the DARK GREEN wire (that goes to the horns....get battery power and blows the horns.

If checking each circuit is required due to the wires are not correctly installed in the bulkhead connectors....MAN....that would just 'tick' me off.

ON the A/C TCS fuse....look at your wiring diagram and check it and see if the wire that is going to whatever the fuse is protecting is NOT grounded. I bet that if your pull the fuse...the inner terminal that holds the fuse in the fuse panel will be grounded.. IF it is....just make sure that the end of this circuit weir is NOT connected to what it is supposed to go to and check it again. IF it is still grounded...you have to find the area where this wire is touching something steel in the cart that is grounded. IF when you disconnect the wire from where it is supposed to go to and there is NO GROUND...then connect the wire terminals ( depending on how many there are int hat circuit) and see which one causes the fuse to blow.

AS for the fuel gauge.....I would make sure that the BRAKE warning light works...if it does...GOOD....IF not...then look at the GAUGE fuse. 0 to 90 ohms is what your sending unit is using to make the fuel gauge work. Assuming that is is good. You want to make sure the rear body wiring harness is connected to the dash harness and that none of the terminals are coming out. And that the GROUND going to the fuel sending unit is GOOD. The 'good' part is that you cans see and manually actuate the float in an empty fuel tank to check the ohms the sending unit is putting out. A good solid bent wire is what I use.

DUB

 

Thanks guys. I pulled the fuse block to find a heavy gauge orange wire and a pink/black wire attached to the a/c TCS fuse. I'm running down the wires and making sure all the connections are correct. I'll be sure to report back.

Chad