I recently purchased a 2019 Cat 299D2 and have been going over it and checking everything over. The stereo inside the cab is intermittent so I am planning to change it. I noticed a small blue plug on the back of the stereo that I am unfamiliar with. It has a small grey wire coming off it. Inside the grey wire is a very small red and black wire. I have traced it under the cab then it goes back inside the cab on the right side and goes up under the headliner. I can not see what it goes to without pulling the head liner. Does anyone know what this wire and plug goes to?
Post a Serial Number. You can have an electrical schematic that will enable you to figure out where it goes yourself.
CAT0299DEFD205351
Check your messages. The radio connection is in Grid H-16 on Page 10. The red & black wires appear to be switched power from the ignition side of the fuse panel, and ground. You need to double check though.
It could be a wire going to an RCA headphone jack remotely located? Just a thought. Usually RCA wires are wires within a wire or Coax.