Radio and AC cutting out

jthunderbird

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So my 97 GTS was down for a bit with a blown timing chain cover gasket and low AC freon.

Finally got it all taken care of by a Viper Tech at my local dealership. Driving it home though, I noticed the AC would be cold then warm then cold then warm... over and over.

Also noticed the radio was turning on and off over and over, seemingly the same pace as the AC going out... seems I have an electrical gremlin. Never had anything like this ever happen to me on this car. I did a search but all I could find were threads on people wanting to replace their radios.

My car did have a subwoofer when I bought it and an amp. I removed the sub and amp but realized that all speakers were using the amp so re-installed it... not sure if it is factory or not.

Anyone have any insight for me? Want to tell me it is a $10 relay and I am good to go would be great :)

JT
 

AZTVR

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The descriptions of the symptoms are not crystal clear. Does it appear that the power to the radio is going off and on, by looking at the display on the radio, i.e. is the radio display going off and on? Or is it just the audio output sound that is going off and on. For the AC issue: Is there any sound difference (turn radio off and listen)
when the AC gets warm and cold? What does the sound change sound like? Does it sound like the electric fan motor blowing the air is turning off and on? Does it just sound like maybe a flapper door in the heater AC box flapping back and forth? Does the engine noise change slightly as if the AC compressor load on the engine is going off and on?
 
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jthunderbird

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Sorry about that.

I didn't actually have any music on the radio which is probably why I didn't notice it right away. But it just appears that the radio loses power and regains power every other second or so... now and then, it would stay on for 4-5 seconds.

The AC was blowing constantly at the same rate but would simply turn warm and cold at the same time as the radio would go out... basically every few seconds, radio would turn off and air would get warm... then radio would come back on and air would get cold... over and over.
 

AZTVR

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If the two symptoms are the result of the same cause, I don't see any electrical circuit commonality between them. The best thing would be to monitor voltage going to the radio and to the AC compressor clutch; but, few people could do that for an intermittent condition. It possibly could be a ground; but, it seems like more circuits would be affected. On my 2002 GTS, the vacuum line that goes to the AC/heater selection door runs right next to the radio (I would think that the 97 is the same.) Especially if the radio has recently been removed, or console, or heat/AC controls have been removed, I could imagine that if things were reinstalled loosely, the connector on the radio could be jiggling from vibration, and a loose vacuum line also jiggling due to the same stuff moving. If you lose vacuum, the door flops away from the AC position.
It seems unlikely; but, that is my best guess at a common cause. Otherwise, many things could cause those symptoms if considered as independent symptoms. As always suggested, make sure that your battery and alternator output voltages are good. Weird things happen if they are low.
 
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jthunderbird

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Didn't want to just leave this thread hanging... It was indeed just a low battery charge issue... wonder if my drive home was longer if it would have recovered itself by being charged up during the drive.

Either way, I put it on a tender a couple of days ago and cranked her up last night. AC and radio worked perfectly... still seems like a weird consequence of somewhat low voltage though enough voltage to turn that big ass motor over and start the car.
 
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