Wipers won't turn completely off

[RussAdams]

I just got into my 1999 Ranger for the first time in a couple weeks.

The windshield wipers won't turn all the way off. Lowest setting I can get is the slowest intermittent setting.

The fast continuous is also not available.

Washer works. Bright beam works. Left and right turn indicators work.

Any suggestions where I should start looking for the cause of this problem?

Thanks! Russ

 

[Brain75]

Since I just beat this to death in my 2nd gen I figured something out, in the 2nd gen (mine) there is an interval govenor - black box inside the dash that runs intermittent, and for some reason low runs through that box, as well as the wash swipe and return to park.

On the 3rd gen+ there is 2 relay's (per the chiltons and haynes books) that do most all of that function, and the computer magic of return to park and wash swipe is in the GEM I believe.
I just returned both of my books to the library and ordered a haynes but it hasn't arrived otherwise I would give you exact spot to look from the book.... user manual have anything on relay location in the fuses section?

It's kind of a pointless test since so much else is screwy, but wash swipe (try to wash and it should do 3 swipes then return to park) as a test is in there....

Since you have power and functionality I assume the fuses, wiring*, linkage, motor, etc all that is good... my bet is one relay (stuck closed) and/or the GEM.

 

[Brain75]

*caveat, just thought of how much the computer is involved.... could even be just a bad ground to GEM. That too would produce most all of the issues (possibly a host of other crap I assume).. So if the relays don't show it, before you get too far into the GEM, just check the ground.

 

[Curious Hound]

*caveat, just thought of how much the computer is involved.... could even be just a bad ground to GEM. That too would produce most all of the issues (possibly a host of other crap I assume).. So if the relays don't show it, before you get too far into the GEM, just check the ground.

Yes. In his newer truck, the interval timer is microprocessor controlled in the GEM or body control module. (I think the name changed some time in later years) there will not be a separate interval governor box.

Are we sure they are operating on the slowest interval setting and not on slow speed? I'm leaning toward this being a problem with the multifunction switch. But if they are actually just running in slow speed and wont6stop, it could be that the contacts in the wiper motor park switch assembly are dirty or bad.

 

[RussAdams]

It was definitely on lowest Intermittent setting. Blades would park for quite awhile then sweep once.

I could not get it to completely turn off.

Various different Intermittent speeds worked like normal.

Low speed continuous sweep worked.

High speed continuous did not work.

After driving for a few minutes with the heater on hot the wipers started working properly.

It's been raining and freezing at night lately. It was cold but above freezing when the problem first happened.

I will go try the wipers this morning and see what happens this morning.

 

[RussAdams]

I have the oem workshop manual... will see if there is a section on the wipers.

 

[RussAdams]

So the wipers are now working completely normally. Went out, started the truck and hit the washer, intermittent wipers (all settings work), continuous wipers (both hi and lo).

Hmmm.

I pulled out the oem workshop manual, volume II, and there is a huge section on troubleshooting the wipers. Thanks for the reminder to RTFM!