Toshiba VRF Console Unit - CN22 Cable Pinout for ESP32 Integration

Hardware
1

Hello HA Community,

I’m working on integrating a Toshiba VRF console unit (model MML-UP0121NHP-E) with Home Assistant using an ESP32, following similar projects like the ESPHome Toshiba Suzumi integration.

Current situation:

  • The main board is not accessible when opening the unit
  • There’s a 5-wire flat ribbon cable protruding from the unit (likely CN22 connector)
  • Wire colors: pink, gray, yellow, brown, white

Goal: Connect an ESP32 to control the device via Home Assistant

Question: Does anyone know the correct pinout for this specific cable/connector? The colors differ from other Toshiba projects I’ve found, where typical colors are blue, yellow, white, red, and the warning about not connecting the outermost pink wire.

Reference project: I’m basing this on existing ESPHome Toshiba integrations, but the wire colors don’t match the documented examples.

Has anyone successfully reverse-engineered this specific model or similar Toshiba VRF console units? Any guidance on:

  • Correct pin assignments (RX, TX, GND, 5V, NC)
  • Which wire to avoid connecting
  • Voltage levels and level shifter requirements

Any help would be greatly appreciated before I start probing with a multimeter.

Thanks in advance!

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2

Hi Bruno. I’m currently solving the same problem, but in my case it’s a RAS-B13J2KVSG-E unit, which should be compatible with the original WRE-T00AH10 wifi control. Because of this, I bought my first simple multimeter with an oscilloscope, so I hope I can figure something out. In my case, there are only 4 wires: white, black, pink, blue. Have you come to any conclusions over the year? Apparently, the colors are quite confusing from what I’m used to.