No windshield wipers or dome light
 

Hey all new member here wanted to say hi quick and dive right in!

98 Ranger 3.0 4x2 Windshield wipers, washer fluid, and interior dome light work randomly. I checked the fuses and they test good. There is no pattern to the problem. Did a quick search and people said fuses, relays, and possibly GEM/CTM module. The problems other people had though with the GEM is usually speedo or other things not working, where in my case it's only the wipers and interior dome light.

Any direction on what to check next including which relays? Thanks

Welcome to the forum

If fuses are OK then GEM would probably be the problem

It operates all interior electrics
i.e. when you turn on the wipers, that switch is ONLY connected to the GEM, not the wiper or washer motor, so GEM gets that signal and then IT activates the wipers.
Same for interior lights, when you open the door that switch is connected to the GEM and GEM then closes the interior light relay.

So all roads lead to the GEM as far as interior electrics.

here are the GEM diagrams for 1998
GEM = generic electronic module, this means that the GEM was specific to each year, model and option package.
So if you want to replace it then you need one from a similar optioned Ranger, so 4x2, and power group

Thanks for the reply. I believe it is the GEM module. I took apart the radio and got to the module, and the interesting part is when I plug the wiring back in everything turns on and windshield wipers go through one cycle, then shut back off. Sounds like the module isn't communicating correctly. Ordered an exact one off ebay (instead of paying the dealer $300) and will see what happens this week.

I have this problem. Do you think it might be a faulty GEM since the door sensor, alarm bells, and windshield wipers started not working all at one time? I have a 1999 Ford Ranger XLT 4x4.

Yes, certainly possible
But check Fuses 10, 20, 25 and 28 in cab fuse box, these all have to do with GEM power

Hey friend, on Friday I experienced something very frightening as a rainstorm came about as I was leaving work. My wiper blades would not come on (I didn't know this when my door sensors stopped working) I checked two fuses at O'Reilly, one being for the wipers and the other being one labeled GEM and they were both fine. At home, I pulled out 25 and saw that it looked intact, but stuck it back in the socket and saw a small spark. After that, I noticed my light was on and now my wiper blades work fine. It's funny how this occured today and your reply came tonight. Anyways, thanks for the help you all provided.

Thanks for the follow up

Power connections on older vehicles build up a type of corrosion that, over time, can cause issues, the simple act of pulling out a fuse and putting it back in CLEANS those connections
Same for sensors or controls in the engine, sensors rarely fail but are often replaced, lol, the only reason the new sensor fixed a problem was because connector was unplugged and plugged back in, CLEANING IT
So unplug and plug in connectors or fuses when you can, before, or when, there is a problem

Reminds me of the old method of blowing on game cartridges to get them to work.
It wasn't the blowing that helped, it was the removal and reseating that actually did the job.