Electric problem
Thread Starter
4th Gear
Joined: Apr 2020
Posts: 4
Likes: 0
Electric problem
Hello. I recently bought a 1981 Chevy corvette. When I got it the tail lights, interior lights, dash lights, radio, and windshield wiper did not work. The brake lights and headlights did. I attempted to replace the ctsy clk fuse but it blew as a soon as I attempted so. I started searching for a ground wire in the middle panel area. Someone on a forum I read unplugging the cigarette light may help. I did so and the interior lights came on. The ctsy fuse no longer blew and the antenna motor started sounding immediately, it would not stop or go down. So I disconnected it near the rear driver speaker. My current concern is getting the radio to work. I replaced the fuse for the tail light and radio and still nothing. Also the radio is an after market one.
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
I would look at the wiring for the radio first-
An aftermarket radio wired incorrectly could cause the problems you are having. The radio was probably wired incorrectly to the cigarette lighter-which affects the courtesy lights. The gray wire at the radio is for the interior lights- often confused as a ground wire for an inexperience installer. The power antenna- OEM set up will not work with an aftermarket radio as it uses a single trigger wire to control it . The wipers and radio are also use the same power source- albeit fused separately.
I'd disconnect the battery- disconnect the wires to the radio -and remove wires that look like they have been added on and see what happens- I'm betting that will solve the problems- unless somebody has put larger fuses in when they blew.
Let us know what happens- and then you can correctly connect the aftermarket radio.
Richard
An aftermarket radio wired incorrectly could cause the problems you are having. The radio was probably wired incorrectly to the cigarette lighter-which affects the courtesy lights. The gray wire at the radio is for the interior lights- often confused as a ground wire for an inexperience installer. The power antenna- OEM set up will not work with an aftermarket radio as it uses a single trigger wire to control it . The wipers and radio are also use the same power source- albeit fused separately.
I'd disconnect the battery- disconnect the wires to the radio -and remove wires that look like they have been added on and see what happens- I'm betting that will solve the problems- unless somebody has put larger fuses in when they blew.
Let us know what happens- and then you can correctly connect the aftermarket radio.
Richard
Melting Slicks
Joined: May 2015
Posts: 2,365
Likes: 428
From: Cape Girardeau Missouri
The "PARK" fuse feeds the "INST" fuse. In other words the parking lamps (headlamp switch pulled out at least one notch) feed the fuse that lights the instrument panel, gauges, shifter, etc. Get your parking lamps (check the fuse first) working and the instrument panel lamps will probably work as well.
As mentioned aftermarket stereos are VERY often wired incorrectly. Few (if any) modern ones use the grey wire for illumination. Also the main (read nearly all of the current) power in modern radios is constant with only the "trigger" wire switched with the ignition. This is the opposite of how our cars are wired. Many just use the CTSY circuit (orange wire) for the constant power but this is a BAD idea because that circuit already powers a lot: interior lights; horn; power door locks; power antenna; cigarette lighter/power outlet and probably a few other things as well.
As mentioned aftermarket stereos are VERY often wired incorrectly. Few (if any) modern ones use the grey wire for illumination. Also the main (read nearly all of the current) power in modern radios is constant with only the "trigger" wire switched with the ignition. This is the opposite of how our cars are wired. Many just use the CTSY circuit (orange wire) for the constant power but this is a BAD idea because that circuit already powers a lot: interior lights; horn; power door locks; power antenna; cigarette lighter/power outlet and probably a few other things as well.
Thread Starter
4th Gear
Joined: Apr 2020
Posts: 4
Likes: 0
I got a manual for the car and looked up the proper wiring. The previous owner had the wiring all messed up. I am still having a problem with the tail light, interior gauge and headlights not going down. I am wondering if It has anything to do with the headlight switch itself.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,114
From: Crossville TN
The headlamp action (raise/lower) has almost NOTHING to do with electricity. It is operated by vacuum servos/vacuum hoses/vacuum relays/etc The only 'electrical' aspect is that the vacuum actuating valve to effect that action is built into the headlamp switch. So, if they TRY to operate, it's probably not the switch giving you trouble.
There is a 'headlamp OVERRIDE' [vacuum] valve at the lower side of the driver's dash panel, just below the steering column. You pull down that black plastic rod and the lights will stay up, even though you turn the headlamp switch OFF. It could be that this valve is in the ON position, so that the headlamps will NOT lower. See if you can push that rod UP to close it....then check the operation of the headlamps with the lamp switch on the dash pad. Otherwise, you have a vacuum system "issue".
There is a 'headlamp OVERRIDE' [vacuum] valve at the lower side of the driver's dash panel, just below the steering column. You pull down that black plastic rod and the lights will stay up, even though you turn the headlamp switch OFF. It could be that this valve is in the ON position, so that the headlamps will NOT lower. See if you can push that rod UP to close it....then check the operation of the headlamps with the lamp switch on the dash pad. Otherwise, you have a vacuum system "issue".
