Originally Posted by liberator221

Installed this same unit over the winter and have the same problem with sometimes staying in warm up cycle. Called Autometer tech line, they told me to connect the brown wire, which is supposed to be an optional switched heater control, to the same ignition source as the red wire. They also said RF interference is a big issue, and verify good ground since it is a boat. I am going to add shielding to the cable going to the sensor and make the wiring changes as they recommend and test it again this weekend.