Mechanics

CHEVROLET SILVERADO RADIO PROBLEM

1999 Chevrolet Silverado • 125,000 miles

I have a battery drain problem. If I do not start the truck for a couple of days that battery is dead. I did a Parasitic Drain test. The battery is drawing 891 mil amps. I have noticed that my radio clock never goes off. It stays on constantly and glows bright at night. So I pulled the 15 amp radio fuse and the meter went to 69 mil amps. When opening up the door and closing it, the interior dome lights work as normal. They stay on for about a minute and then go off, but the clock radio never goes off. The radio is the stock radio, so there has been no change to the wiring. I pulled out the radio and did not see any lose connection. Is there a relay that times out and shuts off the radio or is that internal to the radio? Like I said, the interior dome light and every thing else seems to be functioning as normal, stay off briefly and then shut off. I did not know if anything else ran off of the 15 amp fuse that I pulled, but the radio clock should shut off, correct. Is the clock staying on enough to draw that much amperage and kill my battery, the battery is new.

Thank you
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Djrowland
November 22, 2012.




You found the problem. The display does draw quite a bit of current. Your display is supposed to turn on for only a few seconds when you press the volume knob and the ignition switch is off. Check if the knob is popping back out. If you feel the nice pop of the switch when you release it, the turn-on circuitry inside is shorted. Sorry to say GM decided to no longer allow us to buy radio service manuals after the '94 model year so you're stuck going to the dealer and one of their two grossly over-priced repair centers.

Even 69 milliamps is too high for a drain, but nothing to get excited about. Unless the manufacturer specifies otherwise, 35 ma. Is the maximum allowable. At that rate a good battery will start the engine after sitting for three weeks.

Caradiodoc
Nov 22, 2012.


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