The Dreaded Wipers, Speedo, Dome Light Curse on my 2000 Ranger Please HELP!
 

Happening on my 2000 Ford Ranger XL 4.0 V-6 2wd but different from the typical door ajar light stays on problem that seems very common. I have jumped both door switch leads to rule those switches out. Here is what else I know/have done. 10 amp fuse #26 is good. Anytime I reinsert it both of the 3177 relays click and then the chime rings, the dome light comes on and (if the wiper switch is in the on position) the wipers will sweep until the relays click a second time (about 5 seconds or so). Presumably the speedo is functional as well during that short interval between clicks. Up until just recently when driving the speedo and wipers would suddenly begin working for random distances and then just as suddenly quit working. I bought one new relay and with it installed all of the above mentioned issues remain identical. So as of now, unless the gremlins are in a friendly mood I cannot operate any of these three instruments while driving. Any advice would be greatly appreciated.

Sounds like the wires have been chewed under the fuse block .

Hi schroensr, thanks for that suggestion. I have done a visual inspection of as much of the wiring as I can see clearly and found no evidence of damaged wires (eaten or otherwise). That includes removal of the radio and AC console and the instrument panel. My hunch is that the GEM module was/is faulty or failing/failed because of the way that the three functions operated intermittently while driving up until recently only to become what now seems like permanent inoperability once the initial engine starting sequence is completed. I was hoping that someone familiar with these symptoms would be able to steer me towards OR away from that theory. Those suckers (GEMs) aren't cheap so I would hate to buy and install one only to find out it did not fix my problem. Thanks again schroensr.