Manu

Hello everyone, I have a 2008 Chevy Express 12 passenger, and my radio is not working. The main screen of the stereo does not turn on, however all the other lights do work on the stereo, and in addition the blinker clicker does not click (but the blinkers work). I checked the fuse box underneath the driver seat, and fuse number 8 (rdo/chime) was blown. However, when I tried replacing the fuse it blew again instantly, even though the vehicle was off. I have now taken out the whole front dashboard to take a look at the radio, however I do not see any obvious short circuits. Then again, it is hard to look inside the radio as it is a big sealed box, although I will try opening it if it comes to that. Any ideas as to what the problem actually is? Is the problem with the radio itself or do you think it is with the wiring that is connected to the radio? I found that the fuse blew as soon as I plugged in the black wire on the back of the stereo. So it seems to me that the problem is somewhere in that circuit, however, I'm not interested in taking apart the entire vehicle (even though it looks like I did that already). Any ideas as to what the problem is? Any help would be greatly appreciated.

The guts

The offending black plug (plugged in)

The blue 15 amp popping out is the one (bottom of the photo is towards the front of the van, for orientation)

mountainmanjoe

What model stereo is it?

Measure the resistance on the power pins of the stereo to see if it has a dead short.

You'll need to buy a chime module to get your signal sound back.

Manu

This is the label on top of the stereo.

I don't know which pins to measure.

Replacing the fuse won't fix the clicker?

Manu

The 2 larger pins? If so there's no resistance across them. That means the radio is fried?

mountainmanjoe

Yup probably cooked, which is strange because the OEM units should be fairly robust.

The turn signal sounds and door chimes are generated by the factory GM unit. (sorry I thought the stereo was aftermarket at first)

Manu

OK thanks for your help.

dberladyn

You can take the radio apart. It's not big deal. It's just a circuit board or two depending on the model. You can take it apart and look for any burning on the board. I suspect that it is not the radio, especially if your truck was never 'customised'. If it is all factory. I would suspect a pinched wire or another item on the same circuit. The only other items on the same circuit from my recollection are the Onstar / Satellite Radio. Those boxes are above the drivers right knee under the dash.

What you should do with the radio unplugged is replace the fuse. If the fuse blows, the problem is not the radio. You could go as far as using an ohmmeter to test the constant power and the switched power.

Manu

My van doesn't have onstar or satellite radio, so it isn't that. I'll take it apart tomorrow and see what's going on inside.

Manu

I tried that - I unplugged the radio, put in the fuse, no problem. As soon as I plugged in the black plug into the back of the radio (pictured above) the fuse popped, and the keys weren't even in the ignition.

Manu

So I took it apart, and I can't find any scorch marks or anything like that. Everything looks fine. However, I measured the resistance between the power pins when none of the daughterboards were attached, and there was a few million ohms (although it slowly decreased - capacitors?). When they were all connected, however, I occasionally got a short circuit reading, but then it jumped up to normal resistance. Dunno what's going on.

Anyways, though, I ordered a new stereo with a big screen, along with a backup camera. So even if the stereo isn't broken, I'll be putting in the new one, for the camera and features it has. I'm worried, though, that if the problem isn't the stereo, my new system might get fried - which I definitely do not want.