I have the circuit diagrams for the KX-T123210 which I downloaded from Elektro Tanya some time ago.

I do not know the difference between the KX-123210 and KX-123211D. Seems the power supplies are the same animal. Could this have been to reflect a firmware update?

After completely disassembling the power supply I found that almost ALL of the Rubycon capacitors have leaked.

A fair amount of clean up including replacement of tinned wire jumpers which show corrosion where they enter the PWB to the solder side.

Not sure what I should use to neutralize the electrolyte. Possibly a 50/50 mix of distilled water and white vinegar? I use this to clean up NiCad battery leakage and corrosion.

In a quick search I found EEVblog Electronics Community Forum explains IPA with a follow up of distilled water is best.
What chemical to clean the pcb after leaking capacitors

One crumbling 1/4w resistor. One vertically mounted 1/2w resistor up against a 5 watt resistor which appears to be cracked.

You can also see the greenish electrolyte wetness in image Rubycon1.JPG on the top of the vertically mounted resistor.

Images located here in a Winzip folder:

KX-T123211D Power Supply Images (Dropbox)

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