Hi,
Found the trouble with my Audio. Fiber Op does have light getting to Amp. Removed amp and can see signs of water ingress and damage. I'll post pictures if I can figure it out? Anyway my amp's part number is 2R83-18C808-BA. I assume that the last two letters are revision numbers? Do they matter or will all revisions or all later revisions work on my car? Where can I find TSB on protecting amp from water? I believe I read somewhere else about sealing a body seem and protecting amp with plastic? I also see that some of the replacements offered on ebay are made in Korea while others and my original were made in China; is one known to be better than the other?
It seems to have occurred where the smaller electrolytic capacitors are situated in the circuit board layout.
I suspect the capacitors may have begun leaking some of their electrolyte out through their base vent or leg entry points which will cause some local corrosive activity on surrounding tracks and components.
The copper tracks are somewhat protected by the green masking compound and there is often a protective lacquer applied to the board once all the components were inserted, but I don't see much evidence of additional lacquer in your photos (which probably makes for easier reworking anyway).
Doesn't look that bad so far as saying it is probably repairable, although you would be going on a 2 to 3 hour campaign of replacing all the electros and cleaning the board with IPA as you go, touching up any contaminated solder joints on surrounding components.
Even the TDA3606 if it were found to have a totally rotten pin is likely easy to source and replace.
May be an alternative strategy in case you can't find a suitable replacement readily or economically.
