Radio Draining Battery
Thread Starter
8th Gear
Joined: Apr 2019
Posts: 8
Likes: 0
Radio Draining Battery
I've had a problem with the battery going dead now for a while. I always hooked up a battery tender directly to the battery until I had time to find the cause. While, replacing the factory radio with a factory radio off eBay, I noticed the fins for the amp on the side of the radio were hot. The radio from eBay, the CD player doesn't work, so I didn't have a radio hooked up. No problems with battery drain while radio was out. Put original radio back in, but took out the relay for Bose, thinking the relay was bad. Battery was still draining. Took out the fuse for the radio and no problems with radio drain.
I thought all power, including to the radio was turned off by some time delay relay. The lights go off when the doors are locked. Is there some relay that I should check that might be bad? I always turned off the radio, before turning off the car, so I don't understand how the radio can still get hot. Radio doesn't turn on when the power is off. Trying to figure out if it's the radio or a relay some where. Any ideas?
I thought all power, including to the radio was turned off by some time delay relay. The lights go off when the doors are locked. Is there some relay that I should check that might be bad? I always turned off the radio, before turning off the car, so I don't understand how the radio can still get hot. Radio doesn't turn on when the power is off. Trying to figure out if it's the radio or a relay some where. Any ideas?
Drifting
Joined: Jul 2015
Posts: 1,844
Likes: 375
From: San Jose, CA
There is a fairly common problem in corvettes where, after you disconnect and reconnect the battery, the radio doesn't turn off. I have had this problem twice, I think.
(Coincidentally, both times when parking on the street around the corner of my apartment, in the same spot, where I rarely park. Maybe it's actually the street's fault?)
Maybe there's some sort of magic hotspot in the street, but in any case, I fixed it by pulling the radio fuse (edit: to be explicit, pulling fuse 5 in the passenger footwell fusebox), waiting 15-30 minutes (or more realistically, waiting until the next morning), and putting it back in.
https://www.corvetteforum.com/forums...-turn-off.html
https://www.corvetteforum.com/forums...-shut-off.html
Try this trick first, if that doesn't work, there's more debugging to be had -- whether it's the RAP system, whether it's a faulty door switch, etc.
(Coincidentally, both times when parking on the street around the corner of my apartment, in the same spot, where I rarely park. Maybe it's actually the street's fault?)
Maybe there's some sort of magic hotspot in the street, but in any case, I fixed it by pulling the radio fuse (edit: to be explicit, pulling fuse 5 in the passenger footwell fusebox), waiting 15-30 minutes (or more realistically, waiting until the next morning), and putting it back in.
https://www.corvetteforum.com/forums...-turn-off.html
https://www.corvetteforum.com/forums...-shut-off.html
Try this trick first, if that doesn't work, there's more debugging to be had -- whether it's the RAP system, whether it's a faulty door switch, etc.
Last edited by gimp; Jul 13, 2019 at 03:12 PM.
Thread Starter
8th Gear
Joined: Apr 2019
Posts: 8
Likes: 0
I had the fuse out for the past 2 days and just put it in. It's already draining the battery again. The radio won't come on with the key out, but the fins on the amp will get hot. So the amp for the radio doesn't shutoff, even though the radio is off and the key is out. Any other ideas?
Team Owner
Joined: Jul 2012
Posts: 34,479
Likes: 532
From: Central PA. - - My AR15 identifies as a muzzleloader
I believe in the Beer Fairy
Purely speculation here, just a guess. Maybe a former owner had an aftermarket stereo in the car and remove it before they sold it. They had it wired wrong using the constant power to the head unit instead of the switched power from the ignition. Then when they put the original stereo back in it is running the amp but won't give you a display. That's one possibility. At least worth looking into.
If I had the same problem and I was on a budget, I would go buy a single DIN Kenwood from Crutchfield and call it a day. For around a hundred bucks you will have a fantastic upgrade and you will be rid of the problems that that piece of garbage is giving you. Oh and by the way, it will have FM reception an order of magnitude better then the stock piece of junk.
If I had the same problem and I was on a budget, I would go buy a single DIN Kenwood from Crutchfield and call it a day. For around a hundred bucks you will have a fantastic upgrade and you will be rid of the problems that that piece of garbage is giving you. Oh and by the way, it will have FM reception an order of magnitude better then the stock piece of junk.
Thread Starter
8th Gear
Joined: Apr 2019
Posts: 8
Likes: 0
Purely speculation here, just a guess. Maybe a former owner had an aftermarket stereo in the car and remove it before they sold it. They had it wired wrong using the constant power to the head unit instead of the switched power from the ignition. Then when they put the original stereo back in it is running the amp but won't give you a display. That's one possibility. At least worth looking into.
If I had the same problem and I was on a budget, I would go buy a single DIN Kenwood from Crutchfield and call it a day. For around a hundred bucks you will have a fantastic upgrade and you will be rid of the problems that that piece of garbage is giving you. Oh and by the way, it will have FM reception an order of magnitude better then the stock piece of junk.
If I had the same problem and I was on a budget, I would go buy a single DIN Kenwood from Crutchfield and call it a day. For around a hundred bucks you will have a fantastic upgrade and you will be rid of the problems that that piece of garbage is giving you. Oh and by the way, it will have FM reception an order of magnitude better then the stock piece of junk.
Drifting
Joined: Jul 2015
Posts: 1,844
Likes: 375
From: San Jose, CA
Anyone have the radio power schematics handy? I think we need to figure out which circuit(s) the radio feeds from and when they activate. The way I see it, there are two possibilities right now: either the power supply to the radio is working properly but the radio itself is doing something whack by drawing a ton of power, OR the radio keeps getting fed with the car fully off (doors long closed, lights off, RAP off, etc) which is certainly is not supposed to do.
The fact that pulling fuse 5 seems to have solved the problem entirely makes me think that something might be keeping power on when it's not supposed to.
The fact that pulling fuse 5 seems to have solved the problem entirely makes me think that something might be keeping power on when it's not supposed to.
Thread Starter
8th Gear
Joined: Apr 2019
Posts: 8
Likes: 0
Anyone have the radio power schematics handy? I think we need to figure out which circuit(s) the radio feeds from and when they activate. The way I see it, there are two possibilities right now: either the power supply to the radio is working properly but the radio itself is doing something whack by drawing a ton of power, OR the radio keeps getting fed with the car fully off (doors long closed, lights off, RAP off, etc) which is certainly is not supposed to do.
The fact that pulling fuse 5 seems to have solved the problem entirely makes me think that something might be keeping power on when it's not supposed to.
The fact that pulling fuse 5 seems to have solved the problem entirely makes me think that something might be keeping power on when it's not supposed to.
Melting Slicks
Joined: Jan 2009
Posts: 3,275
Likes: 739
From: Miami FL
Fuse 5 also feeds the trunk-mounted CD changer. Does your car have it? If yes, try disconnecting the changer and reinstalling Fuse 5, and see if the drain dissapears.
Even if you don't have a trunk mounted CD changer, it's also possible that an aftermarket device has been attached to the changer's connector. This connector has been used to provide Aux inputs and aftermarket interfaces. It would be good to double-check.
Even if you don't have a trunk mounted CD changer, it's also possible that an aftermarket device has been attached to the changer's connector. This connector has been used to provide Aux inputs and aftermarket interfaces. It would be good to double-check.
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Thread Starter
8th Gear
Joined: Apr 2019
Posts: 8
Likes: 0
Fuse 5 also feeds the trunk-mounted CD changer. Does your car have it? If yes, try disconnecting the changer and reinstalling Fuse 5, and see if the drain dissapears.
Even if you don't have a trunk mounted CD changer, it's also possible that an aftermarket device has been attached to the changer's connector. This connector has been used to provide Aux inputs and aftermarket interfaces. It would be good to double-check.
Even if you don't have a trunk mounted CD changer, it's also possible that an aftermarket device has been attached to the changer's connector. This connector has been used to provide Aux inputs and aftermarket interfaces. It would be good to double-check.