Car Radio Repair

[IanBerry]

My car radio has been pretty much broken for awhile now, it never plays sound except occasionally when I hit a bump. Figuring it was a loose connection I took it apart and noticed the antenna plug was loose, so I cut it and soldered it directly onto the board. That helped a little bit but it still cut out very frequently. I took it apart again and found that if I pressed down on a specific part of the circuit board, flexing it a little bit, the radio would play sound. It would continue to play sound without fail while I was pressing on it. What the heck is going on? Is it a broken trace? Can I repair that?

[dicky96]

Some pics would be good 

Where are you pressing on the board?

Is this just a radio or does it play CDs or USB or whatever?

If so do you only have the fault on radio or on other sources as well?

Rich

[Armadillo]

Dried out solder joints probably. Just look at every and each of the solder joints for dullness and gaps/cracks on the solder joints.

[mikerj]

Check the solder connections of any power devices that are bolted/clamped to the chassis of the radio (typicaly one or more power amplifier ICs) and also the main ISO connector solder joints.  These joints tend to be put under much more stress than others and are quite prone to cracking with age.

[sokoloff]

As two prior posters indicate, I'd start by resoldering the connections in the area of the board you flex (you can probably just remelt, but if it looks polluted, you can pull off the old solder and apply new with fresh flux)

Though you haven't asked, do not do that with power applied to the radio. (It will be tempting to do so, so you can "quick check" the results. Don't. There's too much risk of creating a short circuit with the iron or with a solder bridge.)