Jl audio 500/1 powers on with low audio out help needed

[ivkata]

newbie needing help i got this amp months ago and i never really get to work on in sinse i was allways have other units to work on.Here is the deal local trade in jl 500/1 slash pcb rev-3 100006 .Before me posting here i spend good 2-3 hours inspecting the unit and i didnot foud and bad power supply or output fets.All resistors near the output are teasted and all with the tolerance.There is no burn marks or signs of previous repair ,when conected to the power supply them amp works but the audio output is very very low -10 watts max.i left it working for good 30 min and no overheating in the power or output side,no current on the speaker conectors.The audio output is clear with no distortion but very low.No ternal or low ohm lights any help is apresiated

[Perry Babin]

The input voltage switch near the RCA input jacks may be in the wrong position. I'm assuming that you have the gain control fully clockwise.

[ivkata]

input voltage sellection is set to low .week aggo i had same rev-3 jl audio for repair and i swaped the input boards but the amp keeps playing very low.The only part that i see must be changed is those large capacitors near output section 1200uf 100v-they have the bubble on the top.I ve seen plenty amps working fine with those capacitors bad.

[Perry Babin]

Is any LED on the top of the amp lit other than the power LED?

[807tubenut]

That bubble is just the plastic blow out shield for the caps vent on the top, they just about always look bubbled, but have nothing to do with the capacitors health state.

[ivkata]

nope when i apply power to the unit power light comes right away .I spend like 30min watching the unit working and at no point there was and termal or low ohm light.No smoking or overheating parts .Audio is clear all the time no distortion but very very low.

[Perry Babin]

Post the voltages on the 10 pin connector near the power/ground terminals. Use the number scheme shown in the attached image. Copy and paste the following list into your reply.


Pin 1:
Pin 2:
Pin 3:
Pin 4:
Pin 5:
Pin 6:
Pin 7:
Pin 8:
Pin 9:
Pin 10:

[ivkata]

Ok perry i got the voltages


Pin 1: 0.00v
Pin 2: 15.1v
Pin 3: 14.6v
Pin 4: 7.5v
Pin 5: 14.5v
Pin 6: 14.5v
Pin 7: 0.7v
Pin 8: 14.4v
Pin 9: 14.4v
Pin 10: 0.00v

[Perry Babin]

Is pin 2 positive or is it negative 15v?

[ivkata]

Its negative 15.1v