Rear ended gauges don’t work.

Likely the wiring itself. Trace wiring from sending unit to Guatemala. I drive company truck, rear end gauges have not worked in years on my truck,,,lots of exposure to salt and ice.

 

I recently found my problem with both rears. I was tracing my wires when I first got the tractor about 14 years ago with one of those sharp pointed test lights. The kind you have to pierce the wire coating to touch the wire for a signal. Well I never sealed the wire and it corroded. So just as 88 says. Start at the sender and work backwards. I don’t think you’ll have to go all the way to Guatemala because the harnesses are made in Mehico, but maybe in Southern Mehico which is pretty close to Guatemala