HELP! How to "hardwire" wiper motor to just run...

[Avery4jc]

I'm leaving Saturday for a trip that will inevitably have some rain/snow and my wipers don't work.
They worked before I did all my dash work this past summer but I haven't had a need for the wipers so I kinda forgot they didn't work... until tonight.

I've looked up wiring diagrams and I understand the motor has power all the time with the key and it's ground path is how it comes on and off and at different speeds.

So it gets power to one of the wires in the harness when I key the truck on but nothing works. I traced the power/ground wire coming in/out of the control module on the column but still nothing. If I hook a test light to the ground out of the module then turn the wiper switch on the light comes on and off but nothing out of the wipers.

Sooooo this is a stupid electric motor. There has to be a way to just power/ground some of these pins and make the dumb thing come on full bore. I messed with it until my hands were numb (it's freezing!) and I can't figure it out. Any help?

Here's what mine looks like...

 

[chevysmithz71]

Better get those ropes ready

 

[Smokinthehippies]

Better get those ropes ready

LOL that would suck to do on the trail. unless you can get a passenger and put them in charge of windshield duty.

 

[Avery4jc]

Thanks for the help you two.

 

[Blue85]

Have you tried bypassing the delay module? You can unplug the connectors from the module (bottom of the steering column) and plug them together.

There are 2 connectors on the motor assembly. The 2-pin is the park switch. If it's not working the wipers won't know when to shut off. For forcing the wipers to work, you don't really need this to work. This diagram seems to be for the dash mounted switch, but the column mounted should be similar:

So the white is the hot wire. Did you measure that AT the wiper motor connector? I assume you checked the fuse? If you have power there, just ground one of the other terminals in that 3-way connector. The purple and gray are low speed and high - I don't know which is which. You should be able to run a wire through one of the grommet holes in the firewall and put a temporary toggle switch somewhere.

But before you start hacking stuff up, pull the connectors apart and clean them up. Contact cleaner is great, but if not work a little 300 grit sandpaper in there and maybe spray it clean with a shot of brake clean. Then fill it with dielectric grease before putting it back together.

If it's not that simple and you want to start fixing it "for real", get an ohmeter and check for continuity from the purple and gray wires to ground as you move the switch. Check for 12V at the terminals on both sides of the module and check for ground passing through the module on the purple and gray.

 

[dremu]

Specific colors depend on the year; Avery, I didn't see in your build thread, what year is the cab/wiper motor? Truck looks like an '81+, but looks can deceive

Note my truck is 70's era with two speed wipers on the dash.

In general, the motor has one wire that stays hot, and you turn it on and off by connecting and disconnecting the ground. Using a test *light*, therefore, won't do you jack as it wants to to test a path to ground. You need a real volt-ohm-meter.

I'm pretty sure the white wire in the bottom three-pack is hot, all the time, fused. Leave that one alone.

I *think* the purple and grey wires in that pack turn the motor on if grounded; one at full speed and one at slow.

I further *think* the two-pack on top with black and grey is for the wiper pump, which you can ignore. Or does yours not have a pump, and the wire is gone or hiding somewhere?

(EDIT: Crap, beaten to the punch... )

-- A

 

[jekquistk5]

I did the toggle switch and just switched the ground. Gives you high and low, just is a pain to stop where you want them.

 

[jekquistk5]

Also you may have to pull the cowl, and manually move the arms to get the motor to go if its been sitting awhile.

 

[Avery4jc]

Thanks guys. I'm getting power with the key to the white wire in the lower 3 pin connector. Fuse is obviously good also (I pulled that first to check it).

I'll try grounding the other two wires in that connector and see if it'll move. Jess could be right. Maybe they're just stuck, its probably been 2 years since I had them on.

 

[Blue85]

I know that when the wipers are frozen to the windshield, I can't even notice whether or not the switch is on... until several miles down the road when the wipers appear to turn themselves on.