kurto

Paging Dr. Willcox.......Wiper motor in the car stopped running after I ran independent grounds from the wiper switch to negative battery terminal, from override switch bracket to frame and cleaning up, re-connecting wiper motor ground.

I bench tested the motor and it would click but not move. I gently probed the mechanism that appeared to be stuck and now it cycles as follows:

Both green & blue wires grounded - runs at high speed
Green wire ungrounded - runs at high speed
Blue wire off - runs at low speed (will not park)

If it helps, the voltage on the wires during bench test is as follows:

Red wire on 3 wire harness: 12V
Brown wire on harness - 12V when motor runs
White (blue on mine) - grounded during test, shows .02 - .03 when motor running.

#1 Blue - grounded - no background volts
#2 Yellow - 12V
#3 Green - grounded - shows .03 when all wires connected, motor running.

When I began the project, I diagnosed the wiper motor in place was for a 69 or later car. I replaced that with a correctly wired Willcox motor for 68. After install the wiper motor can would get hot with key in "on" position, wiper switch off. I always heard clicks at the wiper switch and I believe at the solenoid which would also get warm.

When I started checking all wiring connections, the motor would run at low speed at all 3 positions on the wiper switch, then it would run at high when off, normal at on and then stop at high switch position. Then the motor quit all together - I did replace a blown fuse but it still would not move so I pulled it for bench test.

Any ideas or suggestions are welcome. Thanks....Kurt

0Willcox Corvette

Voltage nor anything else matters not... if you followed my video on doing the bench test and it failed... you need a motor. It's cheaper to get the motor then it is to find the park switch and replace it. There is also a tech page on this on my tech site with detailed instructions for testing... if you followed this to a T.... the motor is bad.

I'd still upload this. http://repairs.willcoxcorvette.com/w...-schematic.pdf

Wiper Motor Bench Test 68 Ver 1


Wiper Motor Bench Test 68 Ver 2 "Follow up"


Great threads on 68 Wiper motors can be found here:

Mister Willcox, 68 wiper motor

68 wiper problems


Willcox

18243

kurto

Thank you sir, appreciate the reply.

Rescue Rogers

If someone had a 69 motor in a 68 and had it working, then they rewired your system to work, thats why your motor is getting hot. Make sure you did the 68 test, then check your wiring. you may have to go back to the 69 motor if the wiring is for a later year

i had a new motor that wouldn't park. It turned out the the retaining clip the held the shaft in wasnt in the slot so the shaft would wobble and when it went to park it had enough movement that it would keep rotating. Since its "bad" take it apart paying attention to were everything belongs and see if anything has come apart inside. Its already broken, you may as well learn a little about it. And disconnect the wiper switch ground. If it worked before you started rewiring then , you may have caused your problem. The wiper switch doesnt have a ground wire on a 68. The case should be grounded through your bezel.

heres a hand drawn circuit diagram I copied from somewhere, it could be an old Willcox diagram. the vertical number boxes delineate the motor on the right and the wiring on the left.

kurto

Having low voltage issues and I don't know why. I picked up a new 68 motor and confirmed it worked w/ a bench test. Also replaced the wiper switch as the internals on the old one were loose (likely from too much testing) and I swapped in a new relay. On to the wiring,

Rescue, I took your advice and disconnected the independent ground wire I installed to the wiper switch as it already has good ground when connected to the lower bezel. I checked the firewall (below blower motor) ground wire running to the wiper motor and its good. The over-ride switch also has good ground and the brown/white stripe wire has 12 volts when rotated clockwise to passenger side (switch is "off" to me as its sending power).

I get the following volt readings on the blue / green wires with over-ride switch in off & on positions. No difference when limit switch wiring is connected and button depressed:

Key On-Switch off Switch On - LOW Switch On - LOW
Blue: 12.05 Volts Blue: .03 Volts Blue: .03 Volts
Yellow: 11.99 Yellow: 11.99 Yellow: 11.99
Yellow: 0.0 Green: .02 Green: .01

Any ideas on what I'm missing with the wiring?

Thanks.....Kurt

Rescue Rogers

With the override switch on the off position so that the wipers would operate normally, when you shut off the wipers, do they slow down or are they staying at the same speed, do you hear a clicking in the motor? When you shut the system off the motor goes to a slower speed an theres a little arm that moves a cam that opens a relay that parks the wipers. if its moving to fast you will hear a clicking as it goes by the relay. With tthe wipers running and you turn off the key, what happens?

Rescue Rogers

see if this helps
http://www.corvetteactioncenter.com/...nosis-697.html

Go to the diagnosis tree, theres a parking section in there