JL 300/2

[PapaZBill]

I have a question about this amp. The low impedance lamp is lit. The install and speakers are checked out and the amp was swapped with another 300/2 and works fine with existing install and speaker system.The problem is in the amp. I work on amps for a living, but am not familiar with this amp.I appreciate any advice.Is it possible to get service schematics? I do not have the amp on hand and helping a friend fix amp remotely.

 

[Perry Babin]

That's generally an indication that the amp has shorted outputs.

It's unlikely that you'll find schematics for the amp.

 

[PapaZBill]

are you famaliar with this amp and do you know what the output devices are, by any chance?

 

[PapaZBill]

I find a thread relating to this JL amp and found out the output mosfets are IRF540. I will check with digikey. Question, do you recommend replacing all of the output mosfets or just the shorted ones?

 

[Perry Babin]

I recommend replacing all of the outputs in the blown channel. I wouldn't replace the others unless there were signs of abuse/overheating of the other transistors.