Topic: Smoke A/C panel connection 79
in Forum: C3 Electrical
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Need some help. With the A/C control in the off position I am getting smoke I am pretty sure from the connection that hooks up the the A/C control switch. The switch w/ max air, vent, def, etc. I can run the ac and everything is fine, but out of the blue w/ the switch in the off position I smell electrical burning and I see a stream of smoke coming out of the ac panel. I pulled all connections off under the panel and cleaned w/ electrical contact cleaner. I though the problem was gone but it came back yesterday. When I saw it I cycled the switch back and forth and it stoped. Any body has had this problem and what should I do?
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Duncanville, TX - USA
Joined: 11/8/2003
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Vette(s): #1-1974 L-48 4spd Cp Med Red Metallic/Black deluxe int w/AC/tilt/tele./p/w-p/b/
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#2-1985 Bright Red/Carmine Cp.L-98/auto
Member: NCRS, NCRS Texas, Corvette Legends of Texas
I'd be really careful!! Don't want that car burning down!
You have one of a couple of issues that could cause this. Either a short in the harness connector, OR a loose connector terminal. Problem is....if the thing is turned completely off, there should really be no power being transmitted. There is one exception, tho...with the A/C switch OFF, the blower motor is still running on SLOW speed. If the terminal connection on that circuit there at the switch is loose, it could create a high amperage draw across the terminal(s).
If you see smoke, you should also see where it comes from, as in a melted/melting connector, or wire.
It's possible the fan switch is bad, or even the ground for the fan isn't grounding properly...
You have one of a couple of issues that could cause this. Either a short in the harness connector, OR a loose connector terminal. Problem is....if the thing is turned completely off, there should really be no power being transmitted. There is one exception, tho...with the A/C switch OFF, the blower motor is still running on SLOW speed. If the terminal connection on that circuit there at the switch is loose, it could create a high amperage draw across the terminal(s).
If you see smoke, you should also see where it comes from, as in a melted/melting connector, or wire.
It's possible the fan switch is bad, or even the ground for the fan isn't grounding properly...
Joel Adams
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Has not gotten that bad to see any melting. I guess I will have to pull both side panels and watch for it to see where the smoke is coming from. When the key is off I am find and I don't keep the battery hooked up.
The fan speed switch is on a different connection by itself.
May have to pull the center console out to take a closer look, very hard to see everything w/ just the side carpet panels off.
Will have to wait for another smoke check?
Lifetime MemberModerator
Duncanville, TX - USA
Joined: 11/8/2003
Posts: 20214
Vette(s): #1-1974 L-48 4spd Cp Med Red Metallic/Black deluxe int w/AC/tilt/tele./p/w-p/b/
Am-Fm/map light National/Regional/Chapter NCRS "Top Flight"
#2-1985 Bright Red/Carmine Cp.L-98/auto
Member: NCRS, NCRS Texas, Corvette Legends of Texas
The fan is still powered up with the A/C off. Don't have a diagram in front of me, but I'm fairly certain it is powered from a different circuit than the normal blower switch. I can check later and see....
Whatever it is....it ain't good!
Whatever it is....it ain't good!
Joel Adams
C3VR Lifetime Member #56
My Link
(click for Texas-sized view!) NCRS
"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"
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Oak Creek, WI - USA
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Vette(s): 1981 Great White Shark. Red Interior, 350/190 hp. PS, PB (SS), A/C CC, T-Tops. Served three years in Active Duty Army, then Retired Air Force after 34 years! Badger State Vettes Car Club. 175,000 Original miles!! Now own a 1998 C-5!
So far, everybody is correct. The fan runs at slow speed even when turned to off. My suggestion is to remove both side panels and center consul and have a good "eye to eye" contact with the connections.
Dan
in Forum: C3 Electrical
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