Today at Atelier Kaz - ex-Honda R&D, F1, Indy/CART engineer

In the mean time, I opened the audio head unit and found this.
Severe acid leakage from the capacitors and some of the tracks were just keeping the continuity with hair line width of remainging track.
No wonder why there were signal issues such as imbalance between R and L channels.




Refurbished another spare AMP and started testing it on the bench but after about 30min, suddenly there was no more output signal.

Looking at the circuit, the mute sense pin at IC U2 pin20 went below the threshold and disabled the output reaching the FETs and thus, no sounds from the speaker.

This circuit is used to prevent the popping loud noise when the AMP is first powered up by using the cap/resistor circuit so replacng the assosiated parts could fix the issue.
However, I was worried about the possibility of issue within the IC that decided not to use this spare AMP.




Instead, proposed the owner to let me install the bench one that I have been using for years temporarily and replace it with either another refurbished or even a new AMP at later date.

As the owner has later spec AMP on the L channel, it may be better to have later spec new one for the R side as well.

There was a company called utronic in Germany that used to sell new Bose AMP.
I know at least one owner bought the AMP from them successfully.
Their website used to show online shop with price and delivery charge for our NSX AMP but it seems that they changed the web design and I can no longer see the same page.
May be I need help from someone who can speak German. May be I need to ask for support from our vendor Procar Specials, Detlef???




Had to scrape off all the acid to inspect the damage caused and then repaired them. Three hard wires with lots of soldering bridges and uprated new capacitors installed.




As the owner is interested in future iPod adaptor installation, strengthened the CD port ACC line as well.
Caps on power filter also replaced.

The volume control module was loose so re-tightened it using blue locktite and applied contact cleaner as a standard procedure to prevent white noise when rotating the volume knob.





Quick bench test before closing the case and happy with the result.
Still small imbalance between R & L ch but far better than before the repair.




While the centre console was out, cleaned the aspirator fan at the A/C CCU cabin temperature sensor as it was making annoying noise.