Interesting issue

[H munster]

Working on a 99 ranger 3.0. 2 wd. Fuel gauge stopped working suddenly. Gauge will work when the A/C is on. I cant find what is common between them that would cause this.

 

[hondaxr650]

I took a quick look in the wiring diagram and the only thing I saw right away is that the gauges and the a/c cycling and pressure cutoff switches share a ground at the left side of the radiator support. Possibly a ground problem to the gauges that is somehow finding a ground through the a/c when it is on???? a/c switches go to the PCM so it may be getting a ground through the PCM somehow when the a/c is on? Just a thought, I may be completely wrong. Fuel sender shares that ground too.

 

[H munster]

I think you are on the right track. Thanks for the info, I dont have a book on this one. Its my secretarys truck, Im trying to help her out.