not charging after water damage
I'm in the same place. I have a touch-4g that's been water damaged and the charging circuit has failed.
I have soaked and cleaned the logic board in alcohol to remove any corrosion.
The unit is functional but the battery won't charge. I have the battery out of the unit and can charge it successfully with a seperate Li-ion charger.
Like you, I'm interested in attempting a DIY repair. I'm looking for anyone who has some details of what the charging curcuit looks like. It doesn't have to be the touch 4g specifically. My guess is that the circuit is probably similar across touch models and possibly some iPhones too.
On my unit, there's a tiny inductor next to the speaker connections on the backside of the lower logic board that looks suspicious (it runs extremely hot when the charger is plugged in), but I'd like to be armed with a few technical details before digging in with test equipment.
If you, or others following this thread, come across some basic info about the charging circuit in iPod touches please do share...
Is this a good question?