When this refrigerator came to light a few months ago, I wondered what happens when the vehicle's engine is shut off. Does the refrigerator keep running (cycling) and keep the contents cold? Would the vehicle's battery management system eventually cut power to the refrigerator in an effort to save the battery?
From my experience, it would only run when the vehicle is running. There is quite a bit of voltage drop when the fridge is running. My refrigerator will start at 12.6 V or greater and will run until the voltage drops below 12.0 V. Without the engine running, it will try start, but when the compressor kicks in, the voltage at the fridge drops below 12.0 V and it shuts off for a few minutes. At this point it is no longer cooling.
To solve this issue I bought this DC/DC converter. It maintains the output at 13.8 V regardless of the input voltage.
HOMELYLIFE Voltage Converter DC...
https://www.amazon.com/dp/B07WFMG11F?ref=ppx_pop_mob_ap_share
The cigarette lighter plug on the refrigerator is connected with spade terminal. I installed spade terminals on this DC/DC converter and put between the lighter plug and the fridge. There was room to mount it to the bottom of the compressor frame with a zip tie.
I also did a few other things:
1. Increased the cigarette lighter timeout from 30 minutes to 4 hours via Forscan
2. Bought a cigarette lighter to SAE cable.
On days when I need it to stay cool while parked, I hook up a battery charger the night before. Conveniently, the cigarette lighter sockets won’t time out if a charger is hooked up to one. I use a 2 amp charger and hook it up to the SAE plug. I leave the plug hanging six inches out the lift gate since I back into my driveway.



