Using clues from other users from all over the Internet, I have been able to find out the MQTT message topic/content to turn on/off the remote climate control on the Nissan Leaf. I'm using on Node-RED, but this is applicable to using MQTT in general.
Message topic: VEHICLEclient/USER/command/homelink
To turn on the remote climate control, the payload is: homelink 1
To turn off the remote climate control, the payload is: homelink 2
The VEHICLE string is the ID of your vehicle. If you don't know how the OVMS is sending it to the MQTT server, subscribe to a topic from the Leaf, and it will be VEHICLEmetric/xnl/cc/remotecool - use the same VEHICLE string on the publishing module.
The USER string is the ID you use for the V2 server configuration.
I hope this saves some time to anyone else using OVMS and MQTT!
Thanks for sharing. I'm looking to setup the same thing with Home Assistant for my 2015 Leaf.
I'm not seeing `/metric/xnl/cc/remotecool` or any other MQTT update come through when I click the "A/C" button on the OVMS app. What topic are you using to check the state and confirm it it was successful?
Also im a bit confused by your MQTT topics. I use the default prefix of `ovms/<username>/<vehicleid>` and see updates at `ovms/<username>/<vehicleid>/metric/v/p/odometer` for example. Do I sent the command to `ovms/<username>/<vehicleid>/command/homelink` or something else?
What I would like to know is when will this be part of the "normal release" firmware for the OVMS module? Specifically, will it be part of the 4G modem upgrade firmware I expect to be released with that new daughterboard?
New 'main' firmware is generally released once every month or so.