Monitoring the Maverick's battery voltage while being towed

I am monitoring the twelve-volt Maverick battery voltage while towing the Maverick behind my motorhome. While my motorhome provides a charging line to that battery, if that charging line fails, the battery's voltage could drop. 
If the battery voltage on the Maverick’s twelve-volt battery falls far enough, the electronics fail. The Maverick falls out of neutral tow mode. In those cases, reports indicate exploding computers, transmission failures, and other issues. I need to ensure that never happens to my truck.

I use a small single-board computer called a Raspberry Pi Zero 2W. That is connected to a voltage sensor (Adafruit INA237) that monitors the Maverick battery voltage. The computer is powered by a USB power pack. Because of the Pi’s low current draw, the USB power pack lasts for days and recharges easily. All that is stuck to the brake controller using Scotch Dual Lock tape. Both the controller and the input to my device are powered straight from the Maverick battery. The data is sent to the motorhome via MQTT.  I have both Starlink and cellular service available through a PEP router.

A Python computer program watches the Maverick battery voltage. Should the voltage fall below a set point, two things happen. An Android app called “ntfy” sends an alert to my phone. That acts like a special text message. That message is sent five times, thirty seconds apart. I also send a message via the MQTT protocol to a Virtual Private Server (VPS). The VPS also sends messages warning me of the problem. The Maverick pings the VPS every thirty seconds and warns me should those pings fail.

The display is a five inch HDMI showing a web page.  The Python program writes the voltage values to the web page.

Inside the motorhome, a Raspberry Pi 5 reads the MQTT, modifies a page on its web server and displays that page on a five inch monitor visible to the driver. It also watches outside, fridge, freezer and inside temperatures. Should any temperature or the charger line to the truck fail, alerts are sent.

The temperatures result from Pi Picos with probes.  For the outside, I take the temperature outside on the passenger side, driver's side and rear.  The lowest temperature is displayed.

MINE WORKS … I don’t care about ...

Many out there are much better at hardware than I am. Those people might choose different hardware, and I’m sure it would work better. That being said, I don’t care. There are many out there with significantly better Python programming skills. Those people might choose other ways to program such an application. That being said, I don’t care. Mine works

To those brave souls who tow without a charge line and brag about it, you’re nuts.

This is a link to the Python program for the Pi Zero W

This is a link to the Python program for the Pi 5