I have a kicker kx850.2 and kx350.4 and both worked fine one day but the next they just wouldn't turn on at all. So I tested all my wiring and it was fine. I took out the amps and tested them in four other cars and they still would not turn on. They just kept on blowing the fuses and thats all that happened. Opened up and nothing looks blown or burnt and everything seems fine. Any sugestions?
The fuses blew after I turn on my radio. All you hear is a pop and then nothing and then smoke from the fuses (on the 350.4 its 2 20 amp fuses and on the 850.2 its 3 40 amp fuses)
Am I able to change the transistors myself? I know a lot about car audio and how to diagnose amps. If so, what transistors do I use?
If you're new to repairing amplifiers, you should read the basic amp repair page (link in sig line below). Read all of it, even the parts that you feel are irrelevant. If you still have questions, let us know.
I know a lot of stuff about amp repair etc and I am an expert at soldering. What transistors do I use to replace the ones in there now?
ok i went to radio shack and bought the same transistors (matched up the numbers) and changed them. It worked fine for about an hour and then same thing happening now. Except now the fuses are blowing before I put in the remote wire. What do i do???
Are you sure that you purchased IRFZ44s at Radio Shack?
Is this the 350 or the 850 that you replaced them in?
Is this the 350 or the 850 that you replaced them in?
Yes im sure I replaced the transistors with the exact same ones. I didn't buy them from radioshack. I called a place that was close to where I live and they gave me the exact same ones. The numbers matched up and it looked the same and everything. I replaced these in the 350.4. It worked fine for about and hour and same thing except now the fuses blow before I put remote trigger to it.
If the fuses blow as soon as you connect battery power, its probably the psu transistors. test them with a multimeter on the ohm setting and see if any of them has different readings or is shorted. you may want someone to verify as i am a rookie lol Edit: you can also connect the amp with a 12v light bulb in seiries, if the bulb lights up it means the amp is drawing exessive current and will blow fuses
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To use a 12v lamp like that, it needs to be a high-power lamp (like a headlamp). The current draw determines the brightness. They can light up a bit and there is no problem. When the headlamp lights to full brightness and remains at full brightness, it generally indicates that there is a problem.
Did you check the gate resistors and the driver transistors before installing the new FETs?
Did you check the gate resistors and the driver transistors before installing the new FETs?
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