Energy audio mighty 1200.1

[Aqeeb127]

Hi im in need of assistance the power supply section was blown so ive replaced the mosfets and the driver transistors but it switches very fast on and off with the power supply mosfets out it powers up correctly and im getting a very fast clicking sound as soon as i apply the remote wire to turn the amp on

 

[twilliar]

Double-check the output section or remove the rectifiers to separate the PS from the output.
This will allow you to proceed without pulling your hair out.

 

[Aqeeb127]

Ok will take it out then will check if its doing the same

 

[Aqeeb127]

I took the rectifiers of and its still doing ing the same thing

 

[Perry Babin]

Which terminal of the PS controller IC is it that's driving the IC into protect?

 

[Aqeeb127]

Mr perry i dont understand but what happens is that the as soon as i apply the remote its like the output fets short out then turns off then on then off the whole time as it pulls the power supply full current limit

 

[Perry Babin]

Are you saying that the output FETs short (as in complete failure) and must be replaced?

Have you tried powering up through a limiter?

 

[Aqeeb127]

It heats up way to fast but i am using a 12v 3 amp supplu

 

[Aqeeb127]

With the 12v 5 amp it heats up faster

 

[Perry Babin]

If it does the same thing with the rectifiers out, pull them.

Post a good quality photo of the power supply drive circuit section.

 

[Aqeeb127]

I will do that later

 

[Aqeeb127]

That the pics i could take

 

[Perry Babin]

That's not much to work with. Read this:
bcae1.com - Car Amplifier Repair Tutorial - The Basics

 

[Aqeeb127]

Ok this is what ive found so far there is 11.something volts dc on the gates of the mosfets and thats way too high then i pulled the fets out and i took the buffer transistors out also then i got 4.5v dc coming out the tl494 im going to post the tl494 voltages as soon as i record them all

 

[Perry Babin]

If it has an emitter-follower driver stage, higher than expected voltage is almost always a problem with the PNP driver. It could be due to a failed transistor or a bad ground on its collector.

 

[Aqeeb127]

Ok im going to change them all out again then check the gate voltage again

 

[Perry Babin]

Why not check them?

If you already replaced them, the ground could be the problem.

 

[Aqeeb127]

They read fine and was soldered properly so i took them out as the 11 volts was right up until the tl494. So when i removed them i got the proper voltage as your tutorial says it need to be ~1/2 vcc for unregulated power supplies

 

[Perry Babin]

Are you sure that you had the correct transistors in each location?

 

[Aqeeb127]

Im pretty sure as the pnp has ground on the collector and the npn has the b+ on the collector