Electrical woes
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Joined: Mar 2018
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From: Topeka, Kansas
Electrical woes
I hadn’t driven the Vette in 6 months. As expected the battery was dead. I have a disconnect on the negative side. I hooked up my battery charger and adjusted it while watching the gauge on the charger. Then SNAP and smoke from under the dash by the pedals.
I had hooked the charger up to the car side of the disconnect and not the battery.
I did manage to charge the battery a bit and got the car started. The wiper fuse was fried. All other seem fine. I have no interior lights now but I have power to the cigar lighter and headlights.
Where should I look to find the melted component. Cannot believe I made such a foolish mistake
I had hooked the charger up to the car side of the disconnect and not the battery.
I did manage to charge the battery a bit and got the car started. The wiper fuse was fried. All other seem fine. I have no interior lights now but I have power to the cigar lighter and headlights.
Where should I look to find the melted component. Cannot believe I made such a foolish mistake
Race Director
Joined: Mar 2017
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From: Virginia
Have you seen this thread? This guy made a great wiring diagram for 1980 C3s.
https://www.corvetteforum.com/forums...ector-pdf.html
Check the fusible links by the starter. It is a replaceable component. Mine had the insulation cooked off, but still passed current. I replaced it anyway. The L82 harness works in L48 cars, and includes extra wires for the aux temp sensor, and costs the same.
https://www.zip-corvette.com/80-l82-...n-harness.html
https://www.corvetteforum.com/forums...ector-pdf.html
Check the fusible links by the starter. It is a replaceable component. Mine had the insulation cooked off, but still passed current. I replaced it anyway. The L82 harness works in L48 cars, and includes extra wires for the aux temp sensor, and costs the same.
https://www.zip-corvette.com/80-l82-...n-harness.html
Race Director
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Well the snap and smoke came from up under the dash. Near the pedals you said. I would start looking where the smoke was.
Race Director
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From: Virginia
I read it again, and am more confused now.
Where did you hook up the charger? How many amps did you push through? A battery can sit in the car, with hundreds of amps available, and nothing bad happens. Did you connect the charger in the engine compartment? To the alternator output, and the engine, for example?
Where did you hook up the charger? How many amps did you push through? A battery can sit in the car, with hundreds of amps available, and nothing bad happens. Did you connect the charger in the engine compartment? To the alternator output, and the engine, for example?
Le Mans Master
Joined: May 2003
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From: Fernandina Beach FL
2023 Restomod of the Year finalist
2020 C3 of the Year Winner - Modified
Just a WAG- a lot of chargers are not filtered very well- throw out a ton of AC. Could have possibly blown one of the capacitors under the dash.
As a kid - my friend's father worked on electronics- had buckets full of capacitors
We made an extension chord with alligator clips and a switch.
We'd hook up a capacitor - throw the switch and they blew up just like firecrackers!!! I'm sure the statue of limitations has run out....
As a kid - my friend's father worked on electronics- had buckets full of capacitors
We made an extension chord with alligator clips and a switch.
We'd hook up a capacitor - throw the switch and they blew up just like firecrackers!!! I'm sure the statue of limitations has run out....
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Joined: Mar 2018
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From: Topeka, Kansas
Bikespace - yeah I know a guy who can draw pictures of electrical things. Funny he still doesn’t know it all yet.
I have a blade switch disconnect at the battery. I usually disconnect when parked. When I attached the charger in the battery box, I attached to the car side of the open disconnect instead of the battery. Instead of running current into the battery I sent it into the car.
Richard 454 - My charger is an vintage Napa Bulkamp industrial unit. I doubt there is any filtering. Capacitor is a good bet.
which one and where could put the car out of commission for a long time. Sucks
I have a blade switch disconnect at the battery. I usually disconnect when parked. When I attached the charger in the battery box, I attached to the car side of the open disconnect instead of the battery. Instead of running current into the battery I sent it into the car.
Richard 454 - My charger is an vintage Napa Bulkamp industrial unit. I doubt there is any filtering. Capacitor is a good bet.
which one and where could put the car out of commission for a long time. Sucks
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Race Director
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From: Virginia
Did you find anything? Perhaps the courtesy timer is fried?
I still can't figure out what happened. Nothing should have happened. Your charger should have detected the absence of a battery, and not put out current. And even if it did, all it should have done was power the clock. Perhaps it spiked voltage, and cooked something.
If you need to dig around under the dash (and it sounds like you do), do yourself a favor and take the driver seat out. 4 bolts. Lay on your back, feet under the rear window, head under the dash with a flashlight and a multimeter. I'd also pull and test each fuse.
Good luck!
I still can't figure out what happened. Nothing should have happened. Your charger should have detected the absence of a battery, and not put out current. And even if it did, all it should have done was power the clock. Perhaps it spiked voltage, and cooked something.
If you need to dig around under the dash (and it sounds like you do), do yourself a favor and take the driver seat out. 4 bolts. Lay on your back, feet under the rear window, head under the dash with a flashlight and a multimeter. I'd also pull and test each fuse.
Good luck!
Le Mans Master
Joined: May 2003
Posts: 8,874
Likes: 3,551
From: Fernandina Beach FL
2023 Restomod of the Year finalist
2020 C3 of the Year Winner - Modified
Did you find anything? Perhaps the courtesy timer is fried?
I still can't figure out what happened. Nothing should have happened. Your charger should have detected the absence of a battery, and not put out current. And even if it did, all it should have done was power the clock. Perhaps it spiked voltage, and cooked something.
If you need to dig around under the dash (and it sounds like you do), do yourself a favor and take the driver seat out. 4 bolts. Lay on your back, feet under the rear window, head under the dash with a flashlight and a multimeter. I'd also pull and test each fuse.
Good luck!
I still can't figure out what happened. Nothing should have happened. Your charger should have detected the absence of a battery, and not put out current. And even if it did, all it should have done was power the clock. Perhaps it spiked voltage, and cooked something.
If you need to dig around under the dash (and it sounds like you do), do yourself a favor and take the driver seat out. 4 bolts. Lay on your back, feet under the rear window, head under the dash with a flashlight and a multimeter. I'd also pull and test each fuse.
Good luck!
Yep- my friend Joey's Dad also had some Amateur Radio Gear- and we thought it was OK to just "use" it- Till the FCC showed up at the door!!!
That was my start- got my Amateur License shortly there after at 11!
Burning Brakes
Joined: Jul 2018
Posts: 979
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From: Maryland
You can safely check out the wiring and components if you have a basic VOM. Disconnect the battery completely - put the VOM in Ohms position and check across the (now disconnected battery leads). Ensure you do not have a short - and if you are good here, you can move on to other suspect circuits. I like to do this at the fuse panel as you can isolate each circuit this way. You can use the basics of Ohms law here to determine the health of each circuit. For instance, if you are checking a 10-amp fused circuit, you would calculate 12/10 = 1.2 ohms would be the minimum resistance you should see (from the fuse panel to ground) before that fused circuit will blow. .
Safety Car
Joined: May 2001
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From: Fairfax Virginia
The Noise and Smoke must have come from something down there. I personally would not use the C3 until I "knew" what happened. I would also put a good fire extinguisher in the car. The Snap and Smoke came from near the pedals under the dash. As so many have suggested and take a good multi meter and climb under the dash and find the source of the "SNAP". I have a much earlier version of a C3 and under the dash and near the pedals would be describing the fuse panel. Something has been damaged and when it was damaged it released smoke and likely smelled foul. I would follow my nose down there and see if that leads you to the part that Snapped and released Smoke Relays don't normally do that and I cant think of anything in the fuse box that would Snap.
Those fusible links like the ones used near the starter motor actually "wear" as they are used and eventually pop easier than they were designed to. I have learned that those fusible links near the starter are the "last protection" for the interior electrical system of the 1968 C3.
Those fusible links like the ones used near the starter motor actually "wear" as they are used and eventually pop easier than they were designed to. I have learned that those fusible links near the starter are the "last protection" for the interior electrical system of the 1968 C3.
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Joined: Mar 2018
Posts: 73
Likes: 36
From: Topeka, Kansas
The car is up and running. I am guessing that the snap and smoke came from the wiper fuse that blew. It was melted good. Doesn’t seem to be a problem with the fused links.
I still don’t have courtesy lights but I do have the cigar lighter. I have not had time to pull the glove box yet to see what the courtesy light timer looks like. Im guessing it is fried.
As suggested I did pull the front seat and poked around under the dash. I didn’t see any melted wires or smoked relays. Then I had my son crawl under there and I iced my back. lol
I’ll keep you all updated. Thanks for the ideas so far.
I still don’t have courtesy lights but I do have the cigar lighter. I have not had time to pull the glove box yet to see what the courtesy light timer looks like. Im guessing it is fried.
As suggested I did pull the front seat and poked around under the dash. I didn’t see any melted wires or smoked relays. Then I had my son crawl under there and I iced my back. lol
I’ll keep you all updated. Thanks for the ideas so far.