Kenwood kac - x521 major problem

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i have a kenwood exceleron kac x521...it came out of one vehicle and sat in a cabinet for a while...when i re-installed it in another car the two 30A fuses blew a couple seconds after hooking everything up.i have a very basic knowledge of electronics, and i have a multimeter...where would the best place to start be?
 
Souns like the power supply is blown in the amp.

First thing you should check is the power supply fets in the amp.

Set your meter to ohms and stick your red probe on leg 1 and stick your black probe to leg 3. Then leave you black probe on leg 3 and stick your red lead on leg 2 (middle leg). You should not red anything near 0 ohms.

Post your results on all of the power supply fets.


leg1 to leg3:
leg1 to leg 2:
leg2 to leg 3:

The image below is a diagram on how to check them
Basic Amplifier Repair - Transistor Test Applet Link
 
here's some new insight to my potential problem...i opened up the amp got the board flipped around and found these burns...any insight???
 

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The transistors sometimes puke soot out the legs like that, will usually clean off. Get the numbers off them and look at MCM. I have the best luck there for those SK Sankens they often are. Those are the outputs. I found some at Littlediode also.
 
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might be a stupid question

i plan on using the amp bridged...is there some odd chance are there unused transistors that i could just "swap" for the burnt up one?? hard to find anyone selling just one skc3856...i was just curious before i bought a new one or 10 to make my minimum...or are there other components i should consider replacing while i'm in there??
 
Instead of replacing the 3856s in the other channel, I'd suggest that you replace the 1492s in the failed channel (if you're only buying/replacing the others to meet the minimum order requirements). The A1492s more likely to need replacing since they were subjected to the same thing that caused the failure of the 3856s.
 
i shouldn't read any resistance across any of the legs of the transistors right?...the right channel reads no resistance and the left channel (the one with the burn mark) reads some on the adjacent transistor to the one that was obviously bad... i will just replace all transistors in that channel...thanks so much for all the help and advice i'm new to the electronics game, but want to learn i truly appreciate the assistance...i'll keep you posted on how it turns out...and have another amp sitting in garage with a problem will post in near future
 
Are you trying to test the transistors in the board? If so, that's not reliable. They'll have to be removed for testing. For the outputs, you should read ~0.6v (on diode check) for legs 1-2 and 1-3 and nothing with the probes reversed. All other probe placement should show an open connection (OL). Read the Basic Transistor Testing page (link below). The outputs are BJTs (Bipolar Junction Transistors).
 
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