Well, this worked like a champ. Removed all 8 and replaced them. Amp is working like new.

 

I have a 1993 Lexus LS400 with the Nakamichi CD controller I had installed about a month ago.Afterward,I had no audio from the CD changer.The business that installed the radio/CD said the amp was ok but the Changer was bad.It will play the CD's good,just no audio.Also,it will not change tracks when you mash the track button.Is there a possibility that a wire or two was crossed?A previous owner had installed a Kenwood CD player in it.So I had it taken out.Now I know why it was installed to begin with.If the wires are hooked up correctly,does anyone know where I can find another Nakamichi CD changer?The part# is as follows,#86275-50060.I found the Nakamichi Radio w/CD button controller about a month ago on Ebay.The radio and cassette plays fine.Also,my small tweeters at the front door corners near the side view mirrors are not working.If anyone should know where I can find the Changer,I sure would appreciate any help.I searched Ebay and all over the internet with no results.I found the Pioneers,but the Nakamichi's is like trying to find that needle in the haystack.Thanks for any help.Al

 

It has been a few years, so I'm not sure if Tament, kurbs, and/or bobbygamer are still around, but my Nak (from 1992!) recently died and I opened the trunk to the sweet smell of fried electronics!

As the pics show, my problem is a bit different (and probably worse) than just some blown FETS - the burnt part of the circuit board (external side) is in the center, but towards what others refer to as the "A" connector (the largest of the three).
From the internal side, you can see that one of the pair of tall black capacitors got way too hot and even the printed circuit connection has melted away!

Soldering/repairing circuit boards is not my area of expertise, so from what you can see, if this salvageable, or not worth the time it would take to fix it?
I don't mind sending it out for repair, but it might be more cost-effective to just start over with another amp.
At press time, used Nak amps seem to be available for $170 - $190.

Also, any guesses as to what happened? It was not a particularly hot day when it failed, and my trunk has never had any leaks.

External side
Internal side

 

Yeah after repairing that amp and buying another and it not working than changing the fets on what would be my 2nd at this point and still getting nothing clearly my head was toast so I changed the whole stereo except I'm still using the factory sub got a cheap precision power 5 channel amp that fits in factory location my nak speakers were pretty bad so I put some pretty nice new speakers mtx thunder 4" in front and some cerwin vega 6.5" for the back (they didn't fit without modification like some 6.5s) and a touch screen head and just ran rca cables to the trunk because the factory amp used a common ground. In the end I'm glad I did it but in your case I would try another amp that one looks like a lost cause if it works good if not you can probably just resell it I have since sold mine otherwise I would let you have it. Sub is still kicking
Had to cut and bend down to fit the cerwin-vegas

 

Friends, I opened up my 92 SC400 Nakamichi amp which was, as is known, looks like suffered water damage. But, the damaged/fried components appear different than what has been discussed in this thread. I am posting pictures of the 2 different parts that are affected... 6 of the resistors - Blue color & 1 of the Black color (Transistor?). Don't know much about circuits/electronics, but, if any one can throw in any suggestions on what these parts are, possible sources to buy, I can procure & attempt to get some one replace the damaged parts. All this effort to give the dead amp a shot to retain factory head unit/amp etc. Appreciate any support. These are 5-6 pieces which fried out - 2 badly
This is just 1 which burned out - T D1414

 

How do open the amp itself?

 

Hello... I’m having the problem with my 20amp fuse popping under the hood. I took the board out and it still looks good besides the points I circled. The fets still looks great! My question is where would y’all start? Can you test the fets while it’s still connected to the board?

 

They can look fine but still not work you need to remove to test them iirc as for the other parts I had to buy a second amp off ebay to figure out the bad ones in mine yours does look salvageable Ive long sold my sc and my spare. Once you figure out what you need you can go to digikey com good luck!