Review on NOCO Genius GEN5X1: Smart Marine Charger, 12V Onboard Battery Charger & Maintainer, 1-Bank, 5-Amp Per Bank, Fully-Automatic with Battery Desulfator & Temperature Compensation by Hector Smith

The charger itself is excellent. No complaints, it works great for my small LiFePO4 battery. BUT. If you're dumb like me and cut the wire to shorten it, you'll probably notice a smaller set of wires between the two power wires in that wire. . "Hmm," you might be thinking, "what are they for?" But you keep going anyway. Turn it on and bam! That does not work. You get a temperature error from the device. These two wires are for the thermistor, which is located in the wire junction where the wire transitions from solid black to red/black. When they are disconnected by the thermistor itself, Genius thinks it's too cold outside to charge. Fortunately, the solution is simple. The thermistor is a negative heat coefficient thermistor, so you can simply strip and twist two tiny wires and the device will come back to life. However, you lose any ambient temperature detection capability and the device just assumes it's nice and hot outside all the time (no low-temp optimized charging). Better than not doing it at all! In short, if you cut a wire, either do so after the wire consists of a red wire and a black wire, or be prepared to lose thermal properties.