Cerwin Vega Mobile 500.1 Amplifier, not in protect mode but doesn't work.

[euroticcustoms]

I bought 2 Memphis Power Reference 12's in a slot ported box with a Cerwin Vega Mobile 500.1 amp, used less than 2 months for $250 in Feb. I own a 3000GT with a very small trunk so I couldn't get the box to fit. Anyway, I bought a 1.25 cu. ft. sealed enclosure for 1 subwoofer until the weather got warmer and I had time to build a box.

Originally the subs were wired parallel at 2 ohms. They're single 4ohm voice coil subs. The amplifier boasts 500 watts RMS at 2 ohms, 250 RMS at 4 ohms. Well, when I stepped down to 1 sub, the amplifier's load decreased by half. Anyway, I didn't touch the amp settings, no distortion whatsoever and it hit HARD. A couple months later the subwoofer started cutting out at low volume levels...turn the volume up and the sub would start working again. It kinda sounded like the voice coil was starting to come unwound. Well, finally the sub quit altogether. The speaker felt "semi" tight, so I swapped it out for the other one. The sub still didn't work. Solid green light on the amp with ignition/radio on. No green light with radio/ignition off as normal. I thought maybe the RCA's had shorted onto the amp body as I had them running under the amplifier and the amp screwed down. I disconnected the RCA's, loosened the amp and inspected the wires - they looked good. I had a buddy pull up beside my car and we ran his RCA's to my amp. No go.

I haven't pulled the amp from the car yet to open the case. Was just wondering if this was a common problem with this amplifier? I'm pretty decent at fixing anything electronic, was just looking to see if anybody had run into this problem? I'm not sure if it's on the input or output side of the amplifier. I don't have the high input plug-in or I'd try that route to try to rule out the RCA input as being defective.

All fuses on the amp are good, it turns on, just no output to sub. Anybody?

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[euroticcustoms]

Alright, I took the case apart this evening and found the problem. It was made in China. The other problem, the tolerance between the board and the case was pretty small in the middle of the amp and there was a cluster of capacitors right in the middle of the board. The solder was really thick and one of the legs on a capacitor was touching the inside of the case and had arced against it. This particular leg was wired in parallel with the other 5 capacitors and was in the same circuit as the positive output on the amplifier. I checked Radio Shack and they didn't have any 1000uF 80V capacitors, the biggest they had was a 1000uF 50V for $2.79 each...I thought about putting 2 50V's in place of the 80V but decided to just put some electrical tape on the inside of the case to see if the amp would work. (I was worried that since the capacitors were wired parallel it may have toasted them all). Well, I put the board back in the case, connected the ground wire, secured all the MOSFET's back to the case with their hold-downs and turned hooked everything back up. Kicked the head unit on and heard some static through the speakers...turned the volume up and heard a pop...I went back there and those MOSFETS were blowing out like sparklers. Toasted 5 out of 8 of the small ones. I don't know jack about an amplifier. Hoping somebody out there might. I didn't have a multmeter available to compare the values of the resistors/capacitors/etc so...I figured I'd take it to work tomorrow and check it on my lunch break. I can get MOSFETS cheap enough, just don't know if it's worth it?