‘79 wipers won’t “park”

[slufkin]

Can’t find this with a search.
Washer pump was broken and someone had cut off the 2 wire plug for the wiper park function, so I bought a reman wiper/washer motor assembly and installed it and replaced the 2 wire plug for the park feature.
Everything (high, low and wash) work perfectly, but when I turn it off the wipers just stop wherever they are instead of going to the park position. (I know- 1st world problems) I have power on one side of the “park switch” when the wipers are off and it passes thru to the other terminal except at the park position- so that seems right. Somehow it’s not getting to the motor. I cleaned terminals and plugs on the dash switch.
I bought a new dash switch- but I got the intermittent one- because the sun sun at LMC told me it would plug in and give me intermittent wipers, which is not true- it takes an extra plug I don’t have.
So- do you all think the switch is my problem? Anyone have a test procedure that will verify before I spend more money?
Also- anyone know a way I can make the intermittent switch work for me?

 

[SirRobyn0]

The park switch is built into the wiper motor. It is not a the switch that you flip inside the truck that is fine. If you want I can detail this later when I have a little more time, but do not get a reman wiper motor there have been big problems with them especially Cardone units. Delco no longer makes them new, so the next best choice is to get a WIA brand new, autozone carries them, orielys can order them and they are available on places like Amazon. Let me know if you want more details.

 

[jd42754]

any idea on wiper motor for a 1973 or how to use a newer motor from 79 up?

 

[SirRobyn0]

Is this a 73 you are working on? I assumed it was the 79 C10 listed on your profile.

 

[SirRobyn0]

To answer your question not really. If you could post picture of them side by side I might be able to come up with some suggestions, but frankly you'd probably be money ahead to purchase the correct new one vs adapting in a used unit that isn't quite right.

 

[slufkin]

Is this a 73 you are working on? I assumed it was the 79 C10 listed on your profile.

No I am working on my 79 K10.
I understand how the park switch works, and my testing shows that it is working fine. I dont know how the power gets from the park switch to the wiper motor. I am assuming that it get there via the dash switch and therein lies my problem, but i would like to confirm that.

 

[SirRobyn0]

No I am working on my 79 K10.
I understand how the park switch works, and my testing shows that it is working fine. I dont know how the power gets from the park switch to the wiper motor. I am assuming that it get there via the dash switch and therein lies my problem, but i would like to confirm that.

I'm not sure we are calling the same parts by the same name. The park switch is inside the motor. What happens is you switch the switch off in the cab, but the park switch inside the motor stays closed until the wipers are in the park position and then opens to cut the power to the motor. I suppose it is possible for the switch in the cab to not shut off but in all honesty I've never seen that happen.

 

[slufkin]

Yeah. The wiper motor has three plugs on it. One is three wire for the wipers (lo-hi), one is two wires for the washers and one is two wires for the park switch.
When you turn the dash switch off it energizes a wire into the park switch. That energy passes thru the park switch-unless the wipers are in the park position. That wire disappears thru the firewall- not sure where it goes. I’m guessing it might go back to the wiper switch on the dash and then get routed to the wiper motor via the normal 3-wire connector.
But I’m not sure if it goes thru that dash switch or not.
I’m wondering if someone has the schematic, or knows a test procedure for the dash switch that might prove that switch good or bad.

 

[SirRobyn0]

Ok, I would hit up the wiring diagrams on this forum, which is located in the Squarebody reference library in order to figure out where those wires in question go.

 

[gmbellew]

you should check out the 79 wiring diagram to be sure, but I bet power is from the fusebox and the switch provides ground. the power to the park switch is likely off the same power as the low speed brush.

 

[yes22]

simple fix, check the wiper motor to firewall ground, to test, ground the wiper motor to a good body ground and see if they park, its not the wiper motor, the system works off of ground not power, the motor has power all the time, the switch just is a ground that causes the wiper to cycle, the park feature is part of the wiper motor circuit inside the motor, after the wiper switch no longer has a ground the motor will stop in its tracks unless it has its own ground to the body, you will see a copper strap that is on one of the wiper motor mounting bolts, take it apart and clean the connection

 

[trukman1]

The park switch is built into the wiper motor. It is not a the switch that you flip inside the truck that is fine. If you want I can detail this later when I have a little more time, but do not get a reman wiper motor there have been big problems with them especially Cardone units. Delco no longer makes them new, so the next best choice is to get a WIA brand new, autozone carries them, orielys can order them and they are available on places like Amazon. Let me know if you want more details.

My buddies '79 didn't "park" the wipers but my '77 and '78 did. Has to do with the motor and/or switch, IIRC.

ETA: Meaning I agree with SirRonyno0!

@nd Edit: Meant to say, "Oh no, I bought a Cardone unit last week for the S10 I inherited from my dad. Now I find out their junk! That's the way it seems to go with me. Should have asked the board before buying and installing!

 

[thebros]

I was having a similar problem but just tightened up the linkage that actually drives the wipers and it fixed the problem. There is a small access hole/slot on the driver's side just above the hood and before the windshield. Just got a wrench in there and tightened up the connection to the motor and it works perfectly now.