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Assembled CN105-to-Grove cable, coiled, in orange braided sleeving with a 5-pin JST connector on one end and a 4-pin Grove HY2.0 connector on the other
Assembled CN105-to-Grove cable, coiled, with its four coloured conductors unsleeved, a 5-pin JST connector on one end and a 4-pin Grove HY2.0 connector on the other
The orange CN105-to-Grove cable routed into the electrical box of a Mitsubishi wall unit, running under a retaining clip and beneath the control-board cover
The orange CN105-to-Grove cable plugged into the CN105 port on a Mitsubishi MVZ-A18AA7 ducted air handler control board
The empty red CN105 serial port on a Mitsubishi indoor unit's control board, with the CN105 label and pins 1 and 5 marked in the silkscreen

5.0 · 7 reviews on Etsy

CN105-to-Grove Cable

Assembled and tested, connecting the CN105 service port inside a Mitsubishi indoor unit to a Grove-style ESP32 board: the Serin Controller, an M5Stack Atom S3 Lite, or a NanoC6. No crimping, no soldering.

20 cm, 1 cable in braided sleeving $13

Buy

Free US shipping $35+Ships in 1–2 days30-day returns

Secure checkout by Shopify, shipped from New Jersey.

Fits your unit?

Before you buy

Will it work with your unit?

The cable plugs into the 5-pin CN105 header, standard on most Mitsubishi Electric wall units, ducted air handlers, and ceiling cassettes.

Which length

20 cm: wall-mounted mini-splits

The compact length lets the cable and the controller fit completely inside the empty space in the indoor unit's plastic housing. Nothing is visible once the front panel is back on.

50 cm: ducted and central air

Enough reach to mount the board outside the unit's metal chassis. SVZ, MVZ, PEAD and PVA air handlers have sheet-metal cabinets that weaken Wi-Fi; mounting the board outside the cabinet solves it.

The orange CN105-to-Grove cable routed into the electrical box of a Mitsubishi wall unit, running under a retaining clip and beneath the control-board cover
20 cm, routed inside the electrical box of a wall unit.
The orange CN105-to-Grove cable plugged into the CN105 port on a Mitsubishi MVZ-A18AA7 ducted air handler control board
50 cm, on a Mitsubishi MVZ-A18AA7 ducted air handler.

Construction and testing

Electrically tested

Every cable's power and communication wires are physically tested before it ships.

Optional braided sleeving

The braided upgrade adds orange PET sleeving with heat shrink at both ends, for abrasion resistance where the cable passes the sheet-metal edges inside the unit. The standard cable has the same tested wiring and connectors without the sleeve.

Correct connectors on both ends

A 5-way JST PAP-05V-S at the HVAC end and a 4-way Grove HY2.0 at the board end, wired so the unit's 12 V rail cannot reach the board.

Shipped from New Jersey

Direct orders ship from the workshop, covered by the store policies. Every four-pack except the $30 standard 20 cm one clears the free US shipping threshold; orders of $35 and up ship free.

Works with

The cable interfaces with the internal CN105 5-pin header, standard on most Mitsubishi Electric models. On the board side it fits the Serin Controller and any Grove-equipped ESP32; the M5Stack Atom S3 Lite and NanoC6 are the two listed boards.

It works with the open-source firmware projects the community has built around this port:

  • MitsubishiCN105ESPHome · Home Assistant, via ESPHome GitHub
  • mUART · the mitsubishi_cn105 ESPHome component GitHub
  • mitsubishi2MQTT · any MQTT broker GitHub
  • SwiCago/HeatPump · the library the rest are built on GitHub

Serin Labs' own firmware builds for ESPHome and Apple Home are free, and the controller is flashable either way.

Build it yourself

The cable uses standard parts and a documented design. The wiring reference provides the complete pinout, harness drawing, and DigiKey part numbers for both connector housings. A cable assembled to that specification works identically; the ready-made option provides the parts already sourced, crimped, sleeved, and tested.

The complete controller

The Serin Controller ships with this cable attached

An ESP32-C6 with the CN105 cable already fitted and tested, from $35. Buy the cable on its own if you already have a Grove-equipped board.

See the controller Wiring reference