I've recently purchased a 2000 F150 Work Series Reg Cab with the 4.2 V6. When I bought it, the windshield wipers didn't work. I chalked it up to a bad motor and decided that it wouldn't be a problem for me to swap it. After breaking a couple clips and getting to the wiper motor assembly, I plugged in my new motor before pulling the motor 'transmission' and tested it. No dice.
This makes me think that it could be the switch for the wipers, however, I've heard that a common problem associated with the wiper switch it also the turn signals and mine work fine.
I've tested the voltage of the connector at the harness for the motor and it's good. The voltage doesn't change if I change the the wiper switch from off/on. I've also popped the little cap off of the turn signal switch (multifunction lever) and cleaned the connection inside; still no dice.
I would rather not pull the multifunction switch and swap it unless I have to since I've already bought a possibly unnecessary wiper motor! What should I do to be positive it's the switch? Is there any way it could be an easy fix? Also, is there a way I can test the new motor safely; like can I hook it up to the battery directly or something?

Thanks!!

 

I would unplug the old/current wiper motor from the harness and jumper wire it straight the to the battery or another 12v power source ....if it the motor works and seems/sounds normal...then it is not the wiper motor.

Have you checked all relays and fuses? Does this have tilt steering wheel?

Is there any other strange electrical things going on?

 

I'll try that, but how am I supposed to connect it to the battery? And I've checked every relay and fuse, and the only other strange electrical problems were a stereo short, bad blower motor, and intermittent gauges, but these were due to a faulty alternator overcharging my battery and have since been fixed. The wipers are the only thing that continue to not work. It does not have tilt wheel.

 

Just run a separate temporary wires (one each, 1 positive and 1 for negative post), from the wiper motor to battery.

Does this sit outside a lot? is there a dampness or small puddle on the drivers side door after a rain?

 

It does sit outside, but it's hard to tell about the puddle since we still have snow on the ground here. And run it through the pos/neg posts in the harness or bypass the harness and go into the wires?

 

by pass the harness, run temporary wires.

gotcha with the snow....lay some cardboard on the drivers side floor (not real tight conforming to the floor), and then lay some paper towels on top of the cardboard over night or whenever it sits for a longer period of time ( just not while being driven). If the paper towel is damp or wet. THEN you have a wind shield leak and probably has affected the GEM module. But you have to address the leak before the GEM

 

Uh, which wire(s) did you check on? One of them is HOT in ACCY/RUN regardless of the wiper switch position and it's only used for the parking function in the motor module.

You really need to understand HOW the thing works.

The switches internal to the MFS tell the GEM module what you want it to do. The GEM module in term actuates several relays as needed in the underhood fuse box to actually control the motor.

I would NOT be hooking any power directly up to the motor without knowing what you're doing. There are, after all 5 different wires on the connector.

 

My issue might be related.

I have to turn on my wipers as soon as I start the truck or they don't work. However, once they are on, they don't turn off unless I shift to neutral or turn off the engine. I've disassembled and cleaned the MFS and the wiper motor. It still isn't working right.