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Problems with Power antenna (1/14)
 9/14/19 9:35pm
Laurel
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Joined: 9/14/2019
Posts: 39

I just bought a 1981 a few months back and have been doing some repairs on the interior and exterior. The problem I'm having is the power antenna will not go up now when I turn the radio on. The antenna was working fine before. I did do some work around the console and replaced the ash tray lid, cigarette lighter and shifter bulb. The car has a new antenna on it and I double checked around the antenna all the wires seem to be in good condition. I have noticed that now when I turn the radio on the relay under the storage compartment behind the passenger seat clicks 1 time it also clicks 1 time when I turn the radio off. Would a bad relay cause this problem ? I even went back into the console area and looked to see if the antenna wire was hooked up to the back of the radio. I need some help I'm lost for an answer.     

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Re: Problems with Power antenna (2/14)
 9/15/19 2:30am
73shark
Standard Member
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Overland Park, KS - USA

Vette(s):
1973 Orange Metallic Coupe (orig owner), L82, 4 spd (WR), PS, (A/C & PW (I installed from wrecked 73)), leather, AM/FM Stereo, ran with '65 FI unit earlier & will again some day.


Joined: 7/9/2003
Posts: 585

If you hear the relay clicking, then that means the radio trigger signal for the antenna is getting to the relay. That leaves one of two possibilities as the cause of the problem. Either the relay contacts are bad or the 12 volt signal to the contacts is missing.

Another possibility is that the relay is good and the 12 volts is going across the contacts but it's not getting to the antenna motor. So you need to check to see that the 12 volts is getting to the antenna motor. If it is and the antenna is not extending then I would suspect a bad antenna motor.

One thing you could try is to jumper across the relay contacts after you pull the relay out of the connector. You could also measure to see that you have 12 volts at the relay contact in the connector.



______________

1973 L-82 4 spd

Re: Problems with Power antenna (3/14)
 9/15/19 12:10pm
Laurel
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Joined: 9/14/2019
Posts: 39

Thanks 73Shark,  You know I thought about it some more after I posted the problem and was thinking the same thing if the relay is clicking I must be getting power to the relay and then the power not going any further than the relay. I also had to have new mufflers put on the car,  but I watched the man doing the job at the muffler shop as he was working on the car. He owns the shop and has been doing this for a long time,  I trust him. I don't remember if I tried to turn the radio on after I left his shop or not. I tried to look under the car at the antenna but it's real hard to see with the muffler in the way and I was unable to get it off,  but what I could see and feel looked and felt like all wires are connected and in good condition.  Like I said the antenna is new I don't know if it's aftermarket or NOS OEM the previous owner told me it was new and it took some time to find it,  it does look new to me. I'm not very good with all this electrical stuff and checking the things you mention, how difficult  would it be for me to check what you say could be the problems ? I think what I'm going to do first is find the plug that goes from the relay to the antenna unplug it and check for power with a test light that should tell me if I have power from the relay correct ? Do you have any idea how difficult it's going to be to find that plug,  how far back should the plug be behind the driver seat and under the carpet ?  I would Greatly appreciate any help on how to check it out. I know I should have a shop manual and I do have one on order but that don't help know.  









|UPDATED|9/15/2019 9:10:17 AM (AZT)|/UPDATED|
Re: Problems with Power antenna (4/14)
 9/15/19 1:34pm
Laurel
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Joined: 9/14/2019
Posts: 39

After reading some other post on this site about original factory power antenna for the 1981 year I do think the antenna I have is a new or NOS antenna from the description of the after market and the Chevrolet antenna in that post. 



|UPDATED|9/15/2019 10:34:27 AM (AZT)|/UPDATED|
Re: Problems with Power antenna (5/14)
 9/16/19 1:56am
73shark
Standard Member
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Overland Park, KS - USA

Vette(s):
1973 Orange Metallic Coupe (orig owner), L82, 4 spd (WR), PS, (A/C & PW (I installed from wrecked 73)), leather, AM/FM Stereo, ran with '65 FI unit earlier & will again some day.


Joined: 7/9/2003
Posts: 585

Assuming that the radio signal is getting to the relay and that's causing the relay click thereby signifying  it's being energized.  The next thing you need to do is to determine if the 12 volts is getting to one side of the contacts. You can do that with your test light or you can use a digital voltmeter. You can pick one of those up at a Harbor Freight for less than $10. If you're getting 12 volts to one side of the relay contacts when the relay is energized, you need to check the other contact which would be the one going to the antenna. If you have 12 volts there and that would indicate an open circuit between the relay and the antenna, an antenna connector problem, or something internal to the motor on the antenna.

The service manual should contain a wiring diagram which will be an immense help.



______________

1973 L-82 4 spd

Re: Problems with Power antenna (6/14)
 9/16/19 8:01am
Laurel
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Joined: 9/14/2019
Posts: 39

73Shark,  With all the problems the power antenna cause like the one I'm having now and the ones that will arise in the future I've been considering removing the power antenna from the car. I can buy a fixed antenna for a 1980 to 1982 Corvette  from Ecklers for about $74.00 dollars with free shipping. I'm in my mid 60s and I just can't bend and twist around like I used to,  getting to that relay is a problem. I've posted a diagram of all the relays in the storage box behind the passenger side seat and the click I'm getting when I turn the radio on and off is from the metal box on the right in the diagram next to the Blue antenna relay. The Blue antenna plug on the right in the diagram is the power in from the radio and the plug on the Left in the diagram is power to the antenna from the relay. I'm wondering and in your opinion if I leave both the in and out plugs to the antenna relay disconnected will that cause any problems ?  I also want to disconnect my anti theft alarm and at this time have the theft fuse at the fuse box out I'm unsure if that has the alarm inactivated or not,  do you think I would be better off replacing the fuse and unplugging the anti theft module to the Left of the antenna relay ?

 

   

 






|UPDATED|9/16/2019 5:01:21 AM (AZT)|/UPDATED|
Re: Problems with Power antenna (7/14)
 9/16/19 1:54pm
73shark
Standard Member
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Overland Park, KS - USA

Vette(s):
1973 Orange Metallic Coupe (orig owner), L82, 4 spd (WR), PS, (A/C & PW (I installed from wrecked 73)), leather, AM/FM Stereo, ran with '65 FI unit earlier & will again some day.


Joined: 7/9/2003
Posts: 585

Since the antenna power is not working anyway, I don't think you need to disconnect anything. As far as the security alarm, leaving the fuse pulled should effectively eliminate it.

As to what caused the initial power antenna failure, I'm always suspicious when someone works on a vehicle to fix something and when you get it back, something else is wrong. Since the antenna is located directly above the driver side muffler, it would be good idea to check the connection on it.



______________

1973 L-82 4 spd

Re: Problems with Power antenna (8/14)
 9/16/19 4:57pm
Laurel
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Joined: 9/14/2019
Posts: 39

Thanks,  I just had the muffler taken off and I'm going to look at the wires a little closer on the antenna motor. I also received my shop manual today and did some checking on the wires at the relay per that manual. I can't get the antenna to come up when I do what the manual recommends so maybe the motor on it is already bad. I also ordered the fixed antenna and as soon as it arrives it's going on. To he** with that power antenna. Once again I appreciate your help with this Thanks and take care.

Re: Problems with Power antenna (9/14)
 9/16/19 7:46pm
73shark
Standard Member
Send Private Message

Overland Park, KS - USA

Vette(s):
1973 Orange Metallic Coupe (orig owner), L82, 4 spd (WR), PS, (A/C & PW (I installed from wrecked 73)), leather, AM/FM Stereo, ran with '65 FI unit earlier & will again some day.


Joined: 7/9/2003
Posts: 585

When you get the antenna out, try hooking 12 volts directly to the motor and see if that has any effect. Hope the new antenna has the same coax connection as the power antenna.



______________

1973 L-82 4 spd

Re: Problems with Power antenna (10/14)
 9/16/19 8:32pm
Laurel
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Joined: 9/14/2019
Posts: 39

I have the power antenna out and yes that's what I'm going to do on Tuesday,  I'll post the findings. No the new antenna has a new cable long enough to reach the radio. I'm going to leave all the old wiring and the power antenna cable in the car, the power antenna cable has a screw together connection just after it gets into the inside of the car. It has a connecting plug for the relay wires  in the same place. I'll just run the new antenna cable in along with the old and up to the radio. 



|UPDATED|9/16/2019 5:32:26 PM (AZT)|/UPDATED|