Dead 450/4 JL Audio Amp? Need advice

[stenda60]

Hi all, I have a 450/5 JL Audio Amp that stopped working mid-song last year. I was hoping it was just a fuse but when I unscrewed the bottom plate all I could see was madness (or genius if you know what you're doing). Wondering if JL has regular fuses I can try to swap out or if anyone can point me in the right direction. Just trying to avoid paying $180 to send it in over a fuse or something simple... Thanks in advance!!

[Perry Babin]

You need to confirm that you have sufficient power supply voltage. With your multimeter set to DC volts, the black meter probe on the ground terminal of the amp (not on the point where the ground wire connected to the vehicle) and the head unit on (so the amp will have remote voltage applied), touch the red probe alternately to the B+ and remote terminals of the amp. If the voltage is below ~11 volts on either the B+ or remote line, you need to check the wiring feeding whichever line is too low. If 'both' the B+ and remote turn-on lines are low and your battery is fully charged, you may have a bad ground connection.