1981 corvette electrical issues help!
Thread Starter
Cruising
Joined: Jan 2017
Posts: 11
Likes: 0
1981 corvette electrical issues help!
Hi, I just recently bought a 1981 corvette. It's winter so I was just messing around with the radio a few times in my garage 2 weeks ago, without ever starting the engine. I would put the windows down, play the radio for awhile, use the power locks and horn, etc. I had to jump start the car a multiple amount of times to use it about a week ago. Just a few days ago, first the power locks stopped working, then the courtesy lights stopped working all together. Now the radio only plays the cassets , not fm or am, and most of the time won't turn on unless I turn the headlights on. I'm scared other things will just stop working. What could the problem be? I'm not very mechanically/ electrically inclined, and don't want to get scammed.
Thread Starter
Cruising
Joined: Jan 2017
Posts: 11
Likes: 0
iv been driving it around for the last few weeks days, and the battery's been doing pretty fine. Things have just stopped working out of no where.
Safety Car
Joined: Jan 2009
Posts: 3,873
Likes: 25
You know, Back in the day we had that stuff on our 81.
turned out that one of the window switches was stuck, pushing the window up all the time. The motor is quiet, so you never would suspect.
Man did the switch get hot too. And drained the batt in an hour.
(must of had a french fry stuck in it...........
)
The remedy was to cut down on the fries. .....
turned out that one of the window switches was stuck, pushing the window up all the time. The motor is quiet, so you never would suspect.
Man did the switch get hot too. And drained the batt in an hour.
(must of had a french fry stuck in it...........
)The remedy was to cut down on the fries. .....
Thread Starter
Cruising
Joined: Jan 2017
Posts: 11
Likes: 0
You know, Back in the day we had that stuff on our 81.
turned out that one of the window switches was stuck, pushing the window up all the time. The motor is quiet, so you never would suspect.
Man did the switch get hot too. And drained the batt in an hour.
(must of had a french fry stuck in it...........)
The remedy was to cut down on the fries. .....
turned out that one of the window switches was stuck, pushing the window up all the time. The motor is quiet, so you never would suspect.
Man did the switch get hot too. And drained the batt in an hour.
(must of had a french fry stuck in it...........
)The remedy was to cut down on the fries. .....
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Thread Starter
Cruising
Joined: Jan 2017
Posts: 11
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with my limited knowledge, I was kind of thinking that may be the problem. But I didn't know why these things just started. Maybe because the cars been driven and turned on more times in the past 4 weeks then it has on the past year ?
Le Mans Master
Joined: Dec 2006
Posts: 8,837
Likes: 1,028
Thread Starter
Cruising
Joined: Jan 2017
Posts: 11
Likes: 0
i plan on brining it to a shop to get the fuses done up. the horn no longer works,and when i honk it (no sound) the radio shuts out for a moment ?? power locks, courtsey lights, and the radio is very on and off. what would you suggest i ask of them to do when getting ti fixed up? thanks alot for the help. iv been thinking everything will just stop working soon lol.
Le Mans Master
Joined: Dec 2006
Posts: 8,837
Likes: 1,028
i plan on brining it to a shop to get the fuses done up. the horn no longer works,and when i honk it (no sound) the radio shuts out for a moment ?? power locks, courtsey lights, and the radio is very on and off. what would you suggest i ask of them to do when getting ti fixed up? thanks alot for the help. iv been thinking everything will just stop working soon lol.
Stock battery cables are copper clad aluminum trash.
Door lock switches and the harness plugs that connect to them corrode due to rain water intrusion.
Door lock actuators go bad because GM mounted them vertical so crap can run in and jamb them up.
Intermittent wiper modules fail.
Alarm modules go bad. Alarm will go off in the middle of the night for no reason.
Choke relay goes bad.
Low fuel light circuit board quits.
Courtesy light timer goes bad and drains the battery.
Oil pressure gauge loses its fluid damping and wiggles.
ECM can go out.
Harness connection on the firewall behind the fuse box can corrode.
Tail light sockets can corrode internally and go whacko.
Flashers quit
Cruise control quits.
Turn signal switch quits.
These are just what I remember over the last 20 years chasing this stuff.
Know whats funny? I am an electrician. 38 years.
Thread Starter
Cruising
Joined: Jan 2017
Posts: 11
Likes: 0
You want a list of electrical things on an 81 that can go bad?
Stock battery cables are copper clad aluminum trash.
Door lock switches and the harness plugs that connect to them corrode due to rain water intrusion.
Door lock actuators go bad because GM mounted them vertical so crap can run in and jamb them up.
Intermittent wiper modules fail.
Alarm modules go bad. Alarm will go off in the middle of the night for no reason.
Choke relay goes bad.
Low fuel light circuit board quits.
Courtesy light timer goes bad and drains the battery.
Oil pressure gauge loses its fluid damping and wiggles.
ECM can go out.
Harness connection on the firewall behind the fuse box can corrode.
Tail light sockets can corrode internally and go whacko.
Flashers quit
Cruise control quits.
Turn signal switch quits.
These are just what I remember over the last 20 years chasing this stuff.
Know whats funny? I am an electrician. 38 years.
Stock battery cables are copper clad aluminum trash.
Door lock switches and the harness plugs that connect to them corrode due to rain water intrusion.
Door lock actuators go bad because GM mounted them vertical so crap can run in and jamb them up.
Intermittent wiper modules fail.
Alarm modules go bad. Alarm will go off in the middle of the night for no reason.
Choke relay goes bad.
Low fuel light circuit board quits.
Courtesy light timer goes bad and drains the battery.
Oil pressure gauge loses its fluid damping and wiggles.
ECM can go out.
Harness connection on the firewall behind the fuse box can corrode.
Tail light sockets can corrode internally and go whacko.
Flashers quit
Cruise control quits.
Turn signal switch quits.
These are just what I remember over the last 20 years chasing this stuff.
Know whats funny? I am an electrician. 38 years.
Le Mans Master
Joined: Dec 2006
Posts: 8,837
Likes: 1,028
Thread Starter
Cruising
Joined: Jan 2017
Posts: 11
Likes: 0
Yes! the radio has to be aftermarket iv been thinking it was for awhile. i couldn't find the version i have, on any online source, nor the Manuel. i honestly have no idea what it is. its just a black radio with two *****, a small green screen (went blank for good about a week ago) has little plastic buttons on the bottom that illuminate to. only plays cassets. it also says corvette in the cassete spot and luminates green there also. i have not found a single reproduction or original looking version of this radio. maybe it could be there to look origianl? the antenna never automatically went up with it since i got it either. could an aftermarket radio do this if not installed correctly? iv read that aftermarket radios in 81's have been known to do this.
Le Mans Master
Joined: Dec 2006
Posts: 8,837
Likes: 1,028
Yes! the radio has to be aftermarket iv been thinking it was for awhile. i couldn't find the version i have, on any online source, nor the Manuel. i honestly have no idea what it is. its just a black radio with two *****, a small green screen (went blank for good about a week ago) has little plastic buttons on the bottom that illuminate to. only plays cassets. it also says corvette in the cassete spot and luminates green there also. i have not found a single reproduction or original looking version of this radio. maybe it could be there to look origianl? the antenna never automatically went up with it since i got it either. could an aftermarket radio do this if not installed correctly? iv read that aftermarket radios in 81's have been known to do this.
Eventually you will have it all sorted out. It just takes $$ and patience.
Melting Slicks
Joined: May 2015
Posts: 2,365
Likes: 428
From: Cape Girardeau Missouri
Everything you've mentioned is part of the CTSY (courtesy) circuit. It is a cobbled up and splice filled circuit that runs throughout the cabin. Orange wires in the cabin are all part of that circuit (+12V always hot).
Find out if your gauge lights also flash as the radio cuts in and out. If so I'd say there's a 95% chance that the problem is the ground connection on the driver door pillar near the headlight switch. That single connection provides ground for nearly everything in the cabin.
If the gauge lights don't cut in and out, then the problem is probably not ground related but somewhere in the courtesy circuit (those orange wires). The first place I would look is the radio and thereabouts as there may be a poor connection/bad splice/etc. from when the aftermarket stereo was installed. Otherwise (and this won't be fun to do yourself or inexpensive to have done) a factory splice in the harness may be bad. If I remember correctly the orange wire leading to the horn relay (above the fuse panel) leads to the first splice (after the fuse) in the courtesy circuit.
Find out if your gauge lights also flash as the radio cuts in and out. If so I'd say there's a 95% chance that the problem is the ground connection on the driver door pillar near the headlight switch. That single connection provides ground for nearly everything in the cabin.
If the gauge lights don't cut in and out, then the problem is probably not ground related but somewhere in the courtesy circuit (those orange wires). The first place I would look is the radio and thereabouts as there may be a poor connection/bad splice/etc. from when the aftermarket stereo was installed. Otherwise (and this won't be fun to do yourself or inexpensive to have done) a factory splice in the harness may be bad. If I remember correctly the orange wire leading to the horn relay (above the fuse panel) leads to the first splice (after the fuse) in the courtesy circuit.