Hey i have a kicker zr240 and a zx460 amplifier and there is a impulse x2i crossover unit in there too. The zr240 runs 2 kicker subwoofers and the zx460 runs all the speakers in the car. I just wired in a new head unit today and was testing it out and after about 10 minutes i turned up the volume and the zr240 started smoking and the music cut out, and the amp got extremely hot to touch. I worked out that i burnt out 2 N-Channel Power MOSFETs which are numbered q35 and q36. I dont know what went wrong and i dont know how to fix it so any help would be greatly appreciated!
Car Audio & Video - Kicker - ZR240 Car Audio Amplifier
Answers & Comments
I hope you got the filter (the ZRX Active Electronic Crossover Module) from within it set on Low Pass, otherwise it has worked as a full range amplifier and when that happens the subs act as shorts at higher frequencies.
You got it shorted because you either have a real short on the cables that connect it to the subs or the impedance of the subs has been too low.
This is an A/B amplifier that has 2 finals working in parallel on each side - you burned one side. You will have to replace the transistors. But you must also check the MOSFET from the power source, there's a big chance it has been fried when the power transistors failed - you will have to replace it also.
Replace all (not just the fried ones) the finals with IRFP048PBF which are the almost identical replacements. You could also upgrade them to Ixys IXTH240N055T or ST STW160N75F3 but if you can't get either of them everyone that has a breakdown voltage of at least 35V (to handle the peaks from the transformer) and the lowest Rd-s ON will do just fine - they sell for less than $5 a piece