iv replaced all eight Power supply fets, checked all resistance before replacing and after.
now for the weird thing.. before i replaced the the fets the board would power up and relay would click(with the only fet that survived out of the eight that were in it when it went up. i tested it and it was very weak.)but i didnt get any sound well needless to say the two drivers were blown well i changed them and well it would still power up with the new ones. i didnt get any ac voltage on the transformer either times ,before or after the new drivers. well i figured it still didnt make enough ac voltage because it was running on one crappy fet, ordered me some 3205's from digikey (10 of them) always get a couple extra and extraordinary packaged chips arrived. now whats weird is after i installed all of the new fets, running on a 10 amp inline fuse. i powered it up and well it flop flops back and fourth power protect power protect about as fast as it took you to read the words. well it makes ac voltage on the transformer but its oscillating voltage and no voltage as fast as its going from power to protect.
im stumped. if anyone can give any ideas to check next.
now for the weird thing.. before i replaced the the fets the board would power up and relay would click(with the only fet that survived out of the eight that were in it when it went up. i tested it and it was very weak.)but i didnt get any sound well needless to say the two drivers were blown well i changed them and well it would still power up with the new ones. i didnt get any ac voltage on the transformer either times ,before or after the new drivers. well i figured it still didnt make enough ac voltage because it was running on one crappy fet, ordered me some 3205's from digikey (10 of them) always get a couple extra and extraordinary packaged chips arrived. now whats weird is after i installed all of the new fets, running on a 10 amp inline fuse. i powered it up and well it flop flops back and fourth power protect power protect about as fast as it took you to read the words. well it makes ac voltage on the transformer but its oscillating voltage and no voltage as fast as its going from power to protect.
im stumped. if anyone can give any ideas to check next.
red board. 04KX1200.1 i took all the power fets out and powered up fine. protect lights then it fades to power and relay clicks. but if i put two fets in(one on each side) it goes back and fourth again. with the fets out i get 4.34vdc on the gate pads. but when i put the fets in it slowly fades up to 2.8v then back down to 0v and then back up.
with the two fets in, the fet on the power input side gets hot fast. they are 3205's from digikey. i also replaced the 100Ohm gate resistors with 47Ohm resistors. same problems though..
with the two fets in, the fet on the power input side gets hot fast. they are 3205's from digikey. i also replaced the 100Ohm gate resistors with 47Ohm resistors. same problems though..
If you're asking for help, you should be patient. It's likely that the problem is unrelated to any of the FETs.
The 100 ohm resistors are OK in many of the kicker amps that use 3205s because they program in extra deadtime.
It's likely that U14 is defective. Find a point near U14 that reads 0 ohms to the negative speaker terminal. The via directly above the '4' in C274 should read 0 ohms. If not find one that does. Connect a jumper from there to pin 3 of U4. With ALL of the FETs in the circuit, do you still have DC on the output filter inductor?
The 100 ohm resistors are OK in many of the kicker amps that use 3205s because they program in extra deadtime.
It's likely that U14 is defective. Find a point near U14 that reads 0 ohms to the negative speaker terminal. The via directly above the '4' in C274 should read 0 ohms. If not find one that does. Connect a jumper from there to pin 3 of U4. With ALL of the FETs in the circuit, do you still have DC on the output filter inductor?
i wasnt being pushy on a response. i really appreciate every word of advice you type. ok i found the small solder pad that is right above the 4 on c274. so u connect the jumper wire to the number 3 leg on u04 right? or is there a part on the board that is just U4?
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