I know this may be a long shot...

Does anyone have the schematics or service manual for the KX-T123211D?

Namely the power supply Part Numbers PQQT4181ZA. Printed on the PWB is PQUP571ZA-2 and KPC 4594V-0

Thank You.

I remember the manual from 20 years ago, but it definitely did not contain schematics or anything like that.

The only thing that could be done in the field was:

Install circuit boards
Attach amphenol's
Attach mod-clip's
Battery backup
RCA connectors Paging/MOH
RS-232C for printer

Anything else was Factory.

Not exactly true, just too many years ago :-) 1232TD_Service

They made a complete service manual for the TD series, so they may have made one for the 123211D. Now it's made of unobtanium.

Carl

The manual we got was this one here.

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)

In viewing your images those are the days the Unit gets shipped back!
It looks like you know what you're doing.

I highly doubt there would be many power supply capacitor failures in new units. Unless of course there was a bad batch of Electrolytic capacitors.

I suppose even Rubycon capacitors are allowed to fail after ±39 years. Curious the Mitsubishi branded capacitors didn't leak.

It will be a great opportunity for me to use my new Hakko FR301-03/P portable hand held de-soldering pump. No more struggling with a one shot solder sucker, and much less worry of scratching up or damaging a unobatium PWB.

Most of the time I believe I know what I must do. Other times I'm not quite so sure.

Finding the spare time to work on projects seems to be less and less.

Let alone dealing with my work space becoming more cluttered