This morning, while completing the install of a Pioneer XM radio adapter (GEX-P900XM) for my Pioneer head unit (DEH P720), I was attaching a power tap to the battery lead on my amplifier (Alpine MRV-F357). As I was loosening the screw on the amp connection, I accidently made contact with the amp case (metal) with my screwdriver, basically connecting battery power to the amp case. It sparked (I know, I have should have disconnected the battery!).

When I turned the system back on, I got nothing out of the front speakers (they worked fine when I tested them just before I did this trick). I tried messing with all the head unit settings but to no avail.

What is the likely damage?:

The front channel electronics of the amplifier?
The head unit?
The front speakers?

I'm pretty skilled with a voltmeter. How can I use it to track down where the damage is? Or should I just take the amplifier out and have it checked at a service center?

 

check the fuses on the amp....

 

Thanks, I'll check them, badboy3600. If they're blown, are they easily obtained?

Damn, I love this board. I post my problem and ten minutes later I have an answer!

 

Yes they are... pretty much any hardware store. Just make sure the number on the blown fuse (5, 10, 15) is the same one you buy. Get a few just in case...

 

Did you try swapping the front/rear inputs to the amp to see if you're getting signal from the HU? I'm guessing that if it's not one of the fuses on the amp, it's an internal component--just suggesting the input swap to verify.

 

Yes, I'll try that after I check the fuses, it they're not blown. Let's hope it's the fuses.

 

Check the fuse under the hood, that's the one I would expect to pop. A few years ago I accidentally tipped over a cup full of pennies onto the terminals of one of my amps (coincidentallly, an Alpine MRV-F400). Big sparks, no more sound.....replaced the fuse, good as new. Still have the amp, going strong in my wife's car.

 

Since it's only the front channels that are not working, the underhood fuse should be ok, and if it's a fuse at all, it's got to be the amp fuse for the front channels.

I'm going to check it tonight when I get home.

 

I feel your pain Rick......I've done that before and nearly hit my head on the trunk! Unfortunately I did "blow" my amp, but Circuit City didn't need to know that...

 

Bad news. Both fuses are ok. When I took the the left front input and connected it to the left rear, nada out of the left rear speaker (which was working fine with left rear input from the HU connected). So, I assume, I've blown the front channels, right?

Where should I take it for repairs? Both Circuit City and Bryn Mawr, which are authorized Alpine dealers are near me.