Hi All,
I am having a problem with the wipers on my 1990 F150. The problem is only the fastest wiper speed (it has two speeds and the intermitant) works. I have replaced the switch and the problem remains. Any help in diagnosing this problem would be appreciated.
Regards, Larry

1990 F150 4x4 SB, XLT Lariat

 

How about the relay?

 

bad circuit board. i believe it's part of the motor and you have to change it all at one.

 

My 92 had a similiar problem! What I did was take the cover off the mechanisim on the wiper motor. Now on the backside of this cover you will find 2-3 contact arms made of brass, give them a good cleaning and bend them out just a bit, not much just enough to make a firmer contact on the control wheel, clean the control wheel also, reinstall the cover and see if that cures the problem! Worked for me!!
Rayolight

 

no no no
hold on here guys.

Rayolight is right for one.
Check that
but the control module which i have to replace on mine is a cause of this.
I read through the forums and found out that the control module is extreemly fragile!

Find it, either repair it or replace it.
IT has a heatsync on it that will fall off if its droped. and i guess the solders come undone on it.
I'm going to try and repair mine.

The motor is probably fine. Mine was bad, but i know for sure my module is bad, cause my wipers cut off after a min, and stop. but when i turn it to the off position. it moves just fine.
pluss the motor is a pain to change.


Go to a junkyard and find an unwrecked truck and pull out the module.
Everyone says its under the dash behidn the switch down twards the ebrake.
I guess in later models its in the glovebox. but im not sure which years it is.

This should fix your problem.

It could be as simple as the 3 contacts being to loose.
So make sure to try that first.
and dont clean off all the grease on the plate. its dielectric greeze, or whichever one it is. i mighta got that wrong. one of the greezes conducts electricity.
Usually fixing those points corrects the problem. But you might have to replace the module, or fix it.
so if you wanna fix it, find osmebody good at soldering, or solder it yourself. I guess they tack solder it on with like 2 or 3 solders, and there weak solder joints at that.
THe machine musta not known how to solder. lol.

 

Good point Talyn
I at first thought it was the module (mines behind the glove box)
Got a replacement and same prob! Kind of interesting both Modules are marked "Do Not Drop" I did take one apart, not much in there, Put back together and still works!

 

talyn, where can you get a new module?(advace, auto zone,etc.)what is exact name of that part?my wiperswork part time!87 150.they willstop in mid stroke for a few seconds then start back,then stop again;continuosly.tried new motor and switch,samo samo.does dash have to come out toreplace it.itsbehind brake pedal on mine.any info will be mighty fine of ya.

 

For the amount of work to take out the wiper motor, dismantle it, and bend and clean contacts, I bought a rebuilt one and turned mine in as a core, for a mere $45 and just swapped it out. I'll dink, tinker, and fabricate almost anything to save a buck because I'm cheap, errr, frugal. But brakes and wipers I just replace parts instead of wondering when its going to break again.

Just my two cents, of course not everyone is obliged to agree.