Wiper problems
Thread Starter
Racer
Joined: Feb 2012
Posts: 256
Likes: 30
Wiper problems
My 73 wipers aren't working. if I push and hold the button, they move. But nothing on low and high speed. At the switch I have 25 volts on two outer terminals nothing on middle spade. At connection to the motor I have 25 volts on either speed. When I ground the switch I get sparks at ground connection. Bigger sparks on high speed. Also the coil and positive side of coil get really hot. I bench tested the motor before install and it worked.
Why would the wipers only work when I push n hold the button? Also I don't need to ground it on that mode.
Why would the wipers only work when I push n hold the button? Also I don't need to ground it on that mode.
Pro
Joined: Jun 2016
Posts: 567
Likes: 82
From: Auckland
Not too familiar with the 73. From what it sounds like and looking at the diagram I found of the 73 it sounds like a faulty switch.
But one thing is for sure. There is a problem with your meter. There is no way you should be getting anywhere near 25v anywhere on your car. If it's not your meter that is at fault then you have far bigger problems to worry about than your wipers.
But one thing is for sure. There is a problem with your meter. There is no way you should be getting anywhere near 25v anywhere on your car. If it's not your meter that is at fault then you have far bigger problems to worry about than your wipers.
Former Vendor
Joined: Aug 2006
Posts: 76,656
Likes: 1,852
From: Jeffersonville Indiana 812-288-7103
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
First I'd check your meter, 25 volts on a 12 volt system isn't working for me.
Your system is not nearly as complicated at the earlier design, below is a schematic to help you. But you should verify that the motor has a good ground, you can do this by testing the ground on the motor or simply by running a ground from the engine to the wiper motor housing. You should also verify that the switch is grounded. If the center dash bezel is broke at the thin spots then you'll need to jumper a wire from the wiper switch to the lower portion of the small gauge housing. The wiper switch picks up its ground through the dash bezel.
Willcox
Your system is not nearly as complicated at the earlier design, below is a schematic to help you. But you should verify that the motor has a good ground, you can do this by testing the ground on the motor or simply by running a ground from the engine to the wiper motor housing. You should also verify that the switch is grounded. If the center dash bezel is broke at the thin spots then you'll need to jumper a wire from the wiper switch to the lower portion of the small gauge housing. The wiper switch picks up its ground through the dash bezel.
Willcox
Thread Starter
Racer
Joined: Feb 2012
Posts: 256
Likes: 30
my mistake its 12v.ill try ground from wiper motor to engine. i ground switch to bezel housing and i get small sparks at ground. why would the positive coil get hot when i switch on power? i feel maybe something is stuck inside the wiper motor.
Thread Starter
Racer
Joined: Feb 2012
Posts: 256
Likes: 30
after further inspection and watching Wilcox video on bench testing the motor I found the switch to be at fault. You were right. When I connect the lead coming from the firewall direct, I get power to the motor. I tried cleaning out the switch but it wouldn't work. So I'll order one and update.
Last edited by Omarsvette; Aug 20, 2016 at 09:57 AM.
