Wipers, one last try:
Former Vendor
Joined: Aug 2006
Posts: 76,656
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From: Jeffersonville Indiana 812-288-7103
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
Okay..
Now on the bench... do the following:
Connect the wire as shown in A.
Connect ground wires to C E and F
Connect power to D
Then connect power to B.
The motor should run in low speed. If it doesn't then the issue is the wiper motor.
If it does, then the issue is in the car.
Willcox
Now on the bench... do the following:
Connect the wire as shown in A.
Connect ground wires to C E and F
Connect power to D
Then connect power to B.
The motor should run in low speed. If it doesn't then the issue is the wiper motor.
If it does, then the issue is in the car.
Willcox
Burning Brakes
Joined: Apr 2008
Posts: 1,222
Likes: 93
From: shelbyville West Michigan
just remember it may be a rebuild and not wired correctly even if the GM # is correct. went through this on my '68 and Wilcox's tutorial saved the day...even the replacement I bought from the parts store needed to be re-done to work correctly. so if you do go that route, pay attention to his documentation.
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Team Owner
Joined: Jul 2008
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From: In limbo
St. Jude Donor '13-'15, '17 thru '22
Okay..
Now on the bench... do the following:
Connect the wire as shown in A.
Connect ground wires to C E and F
Connect power to D
Then connect power to B.
The motor should run in low speed. If it doesn't then the issue is the wiper motor.
If it does, then the issue is in the car.
Willcox
Now on the bench... do the following:
Connect the wire as shown in A.
Connect ground wires to C E and F
Connect power to D
Then connect power to B.
The motor should run in low speed. If it doesn't then the issue is the wiper motor.
If it does, then the issue is in the car.
Willcox
I had a friend over tonight to play with the motor, since he likes stuff like this and it was a good excuse to drink beer. I would call the testing session a partial success. When we followed the directions above, the motor did, in fact, run at low speed. So, that was a success.
Then, we referenced the general bench test instructions from the Willcox site, and played with high speed and parking. We got it to run on high speed a few times, and to park a few times, but parking was unquestionably unreliable. We did something that caused some smoke to come out of the motor once, but could not re-create it, etc. When it would not park, we would shut off the motor, and I would rotate the plastic wheel on the parking switch by hand, and then it would park once or twice, before not parking again.
At the end of our play session, we decided that the motor was, in fact, "working", but not exactly what I want in my car when I am hundreds of miles from home. So, I want to get a rebuilt one (will order it tomorrow), but I think we need to assume there is some problem in the car.
Please let me know if you have any guidance on where to go from here.
Thanks!
PK
Former Vendor
Joined: Aug 2006
Posts: 76,656
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From: Jeffersonville Indiana 812-288-7103
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
Smoke happens when you are in run on... (I think I illustrated that in the video) where the motor runs and clicks hard.. Don't worry, if you don't do it a long time it'll be fine. The smoke comes from the resistor.
But if the motor isn't parking, you have two choices.. find a park switch or buy a new motor. Personally, I'd buy the new motor without a core. The only thing I'm worried about the new motor is they were on backorder and I can't get an answer on the stock status of them right now. I've posted both links below though. I know I have the rebuilt in stock.
Now that you know the motor is in working condition though you could use the car wiring on it and see if it works off the car. If you are replacing the motor, then don't mount it... just hook up the wires and hold it in your hand... it should respond the same as the bench test.
https://willcoxcorvette.com/corvette...-rebuilt-69-72 Rebuilt w/core
https://willcoxcorvette.com/wiper-mo...-no-core-26559 New, No Core.
Willcox
But if the motor isn't parking, you have two choices.. find a park switch or buy a new motor. Personally, I'd buy the new motor without a core. The only thing I'm worried about the new motor is they were on backorder and I can't get an answer on the stock status of them right now. I've posted both links below though. I know I have the rebuilt in stock.
Now that you know the motor is in working condition though you could use the car wiring on it and see if it works off the car. If you are replacing the motor, then don't mount it... just hook up the wires and hold it in your hand... it should respond the same as the bench test.
https://willcoxcorvette.com/corvette...-rebuilt-69-72 Rebuilt w/core
https://willcoxcorvette.com/wiper-mo...-no-core-26559 New, No Core.
Willcox
Thread Starter
Team Owner
Joined: Jul 2008
Posts: 23,419
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From: In limbo
St. Jude Donor '13-'15, '17 thru '22
Okay..
Now on the bench... do the following:
Connect the wire as shown in A.
Connect ground wires to C E and F
Connect power to D
Then connect power to B.
The motor should run in low speed. If it doesn't then the issue is the wiper motor.
If it does, then the issue is in the car.
Willcox
Now on the bench... do the following:
Connect the wire as shown in A.
Connect ground wires to C E and F
Connect power to D
Then connect power to B.
The motor should run in low speed. If it doesn't then the issue is the wiper motor.
If it does, then the issue is in the car.
Willcox
Before undoing the bench test connectors, I disconnected the connection at A in the above picture. I then tested the end closer to the wiper motor body (the side without the red splice on it. It showed no volts, and full continuity to ground.
I then connected the motor to the car's wires, and that same wire showed 12.7 volts, and no continuity to ground. Any ideas what has gone wrong here?
Thread Starter
Team Owner
Joined: Jul 2008
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From: In limbo
St. Jude Donor '13-'15, '17 thru '22
Hold the phone . . . . (does anyone use that phrase anymore?)
A long session of looking at the wiring diagram with a magnifying glass (I'm not getting any younger), lead me to look at the wires in the car again. I want to look at it again tomorrow when I have not had this level of beer, but I got ground where I wanted it. I'm sure I will have more questions going forward, but I am guessing I'll get the wiper motor running in the car.
A long session of looking at the wiring diagram with a magnifying glass (I'm not getting any younger), lead me to look at the wires in the car again. I want to look at it again tomorrow when I have not had this level of beer, but I got ground where I wanted it. I'm sure I will have more questions going forward, but I am guessing I'll get the wiper motor running in the car.
Former Vendor
Joined: Aug 2006
Posts: 76,656
Likes: 1,853
From: Jeffersonville Indiana 812-288-7103
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
Hold the phone . . . . (does anyone use that phrase anymore?)
A long session of looking at the wiring diagram with a magnifying glass (I'm not getting any younger), lead me to look at the wires in the car again. I want to look at it again tomorrow when I have not had this level of beer, but I got ground where I wanted it. I'm sure I will have more questions going forward, but I am guessing I'll get the wiper motor running in the car.
A long session of looking at the wiring diagram with a magnifying glass (I'm not getting any younger), lead me to look at the wires in the car again. I want to look at it again tomorrow when I have not had this level of beer, but I got ground where I wanted it. I'm sure I will have more questions going forward, but I am guessing I'll get the wiper motor running in the car.
I'm in Maine for three weeks but I'll keep checking back..
Thread Starter
Team Owner
Joined: Jul 2008
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From: In limbo
St. Jude Donor '13-'15, '17 thru '22
BUT, putting it back in the car, I still had the short-circuit problem that I did NOT have on the bench. So something has to be screwy with the wiring in the car.
At the end of last night, I seemed to have gotten rid of the short circuit, and everything tested in the car like it did on the bench. I want to go over it again before I connect to full power; I could do that tonight, but my son will be home tomorrow, and he is better at electrical things than I am. I think now is a good time to have him look everything over before running full battery juice through a system that recently had a known short.
Thanks for all the help to date! Have fun in Maine! Hopefully I'll be out driving the car by the time you get back to the office!
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Thread Starter
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From: In limbo
St. Jude Donor '13-'15, '17 thru '22
Well, my curiosity got the better of me, and I went down to the garage to play. The wiper motor does not work in the car. 
New pic:
I'm pretty sure this is the way things were wired before I changed the wiring harness (because I took pictures and followed them), but I could have effed up. First of all, there is a 3 prong connector at the bottom left of the photo with a dark blue and medium green wire connected to it, that has an empty tab. What is this (I can't seem to find it on my wiring diagram), and what wire belongs on the empty tab?
Secondly, the ground wire connected to the wiper motor looks like it doesn't belong there. It has a locking tab on it like the red-with-a-white-stripe wire, but isn't in a connector like that one is.
Thirdly, I'm getting voltage on the light blue wire in the 1-2-3 connector, where I think I should be getting ground.
Any ideas?
New pic:
I'm pretty sure this is the way things were wired before I changed the wiring harness (because I took pictures and followed them), but I could have effed up. First of all, there is a 3 prong connector at the bottom left of the photo with a dark blue and medium green wire connected to it, that has an empty tab. What is this (I can't seem to find it on my wiring diagram), and what wire belongs on the empty tab?
Secondly, the ground wire connected to the wiper motor looks like it doesn't belong there. It has a locking tab on it like the red-with-a-white-stripe wire, but isn't in a connector like that one is.
Thirdly, I'm getting voltage on the light blue wire in the 1-2-3 connector, where I think I should be getting ground.
Any ideas?
Last edited by Derrick Reynolds; Jun 30, 2017 at 08:15 PM.
Instructor
Joined: Jun 2015
Posts: 212
Likes: 29
From: State College Pennsylvania
I'm pretty sure this is the way things were wired before I changed the wiring harness (because I took pictures and followed them), but I could have effed up. First of all, there is a 3 prong connector at the bottom left of the photo with a dark blue and medium green wire connected to it, that has an empty tab. What is this (I can't seem to find it on my wiring diagram), and what wire belongs on the empty tab?
Secondly, the ground wire connected to the wiper motor looks like it doesn't belong there. It has a locking tab on it like the red-with-a-white-stripe wire, but isn't in a connector like that one is.
Thirdly, I'm getting voltage on the light blue wire in the 1-2-3 connector, where I think I should be getting ground.
Any ideas?
Second, you definitely need that tab grounded. The connector may not be original, as it looks like the PO worked on the wiring a little bit.
Third, when the wiper switch is off, the blue wire shouldn't be grounded. When the switch is on low and high, it should be grounded.
If moving the wiper switch doesn't work to ground the blue wire, either the switch is bad (or ungrounded) or the circuit is open between the switch and the motor. In that case, make sure the relay clicks when the key is on (engine off) and you move the wiper switch between off and on to try and isolate the issue
Last edited by D_Williams; Jul 1, 2017 at 11:27 AM.
Former Vendor
Joined: Aug 2006
Posts: 76,656
Likes: 1,853
From: Jeffersonville Indiana 812-288-7103
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
Well, my curiosity got the better of me, and I went down to the garage to play. The wiper motor does not work in the car.
New pic:
I'm pretty sure this is the way things were wired before I changed the wiring harness (because I took pictures and followed them), but I could have effed up. First of all, there is a 3 prong connector at the bottom left of the photo with a dark blue and medium green wire connected to it, that has an empty tab. What is this (I can't seem to find it on my wiring diagram), and what wire belongs on the empty tab?
Secondly, the ground wire connected to the wiper motor looks like it doesn't belong there. It has a locking tab on it like the red-with-a-white-stripe wire, but isn't in a connector like that one is.
Thirdly, I'm getting voltage on the light blue wire in the 1-2-3 connector, where I think I should be getting ground.
Any ideas?
New pic:
I'm pretty sure this is the way things were wired before I changed the wiring harness (because I took pictures and followed them), but I could have effed up. First of all, there is a 3 prong connector at the bottom left of the photo with a dark blue and medium green wire connected to it, that has an empty tab. What is this (I can't seem to find it on my wiring diagram), and what wire belongs on the empty tab?
Secondly, the ground wire connected to the wiper motor looks like it doesn't belong there. It has a locking tab on it like the red-with-a-white-stripe wire, but isn't in a connector like that one is.
Thirdly, I'm getting voltage on the light blue wire in the 1-2-3 connector, where I think I should be getting ground.
Any ideas?
Ernie
Thread Starter
Team Owner
Joined: Jul 2008
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From: In limbo
St. Jude Donor '13-'15, '17 thru '22
It did not park RELIABLY. It parked several times, but failed to park a couple of times. When it failed to park, I twisted the plastic **** looking thing to the next ratchet with my fingers, and it would park.
Thread Starter
Team Owner
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From: In limbo
St. Jude Donor '13-'15, '17 thru '22
Third, when the wiper switch is off, the blue wire shouldn't be grounded. When the switch is on low and high, it should be grounded.
If moving the wiper switch doesn't work to ground the blue wire, either the switch is bad (or ungrounded) or the circuit is open between the switch and the motor. In that case, make sure the relay clicks when the key is on (engine off) and you move the wiper switch between off and on to try and isolate the issue
Do you have a '70 car? Can I get a picture of the connections at the three prong connector near the wiper motor?
Thanks.
PK
Instructor
Joined: Jun 2015
Posts: 212
Likes: 29
From: State College Pennsylvania
I have tested the switch and the solenoid as instructed in the Willcox videos. Both tested fine, which is not surprising since the wipers worked prior to changing the blower/wiper harness.
Do you have a '70 car? Can I get a picture of the connections at the three prong connector near the wiper motor?
Thanks.
PK
Do you have a '70 car? Can I get a picture of the connections at the three prong connector near the wiper motor?
Thanks.
PK
Here is a picture of the connections, let me know if there is anything more specific you want.
Is the relay clicking when you move the wiper switch? That will help narrow down where the issue is.
Thread Starter
Team Owner
Joined: Jul 2008
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From: In limbo
St. Jude Donor '13-'15, '17 thru '22
I know the relay works because I have heard it click when I flip the switch. But honestly, I have screwed around so much recently that I need to re-test to say for sure that it does in the current wiring. I will try to get to that tonight.
Thanks.
PK
Burning Brakes
Joined: Nov 2006
Posts: 893
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From: Orange Park Florida
Be absolutely sure the "ground" wire actually is a ground. Frame ground for the wiper motor originates from the starter... It is black, but so is the hot wire from the battery to the starter. I've seen many instances where someone replaces the starter and connects all black wires to the "hot" terminal.. Check it out.
Just an idea..
Just an idea..
Instructor
Joined: Jun 2015
Posts: 212
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From: State College Pennsylvania
On the right side of your picture is a connector with three tabs. I have the same one, and two of the prongs are connected to a funny angled connector I described above. But the third one, has no connection on my car (my picture in my post #29, lower left, you can see the empty tab). I can see something is connected there in your picture, but I can't see the wire coming out of it. What color is it? Where does it go?
I know the relay works because I have heard it click when I flip the switch. But honestly, I have screwed around so much recently that I need to re-test to say for sure that it does in the current wiring. I will try to get to that tonight.
Thanks.
PK
I know the relay works because I have heard it click when I flip the switch. But honestly, I have screwed around so much recently that I need to re-test to say for sure that it does in the current wiring. I will try to get to that tonight.
Thanks.
PK
Also, JimT makes a good suggestion. Make sure that the motor ground is actually grounded and that the yellow and red wires to the motor have 12V when the car is on (engine can be off) and the wiper door is up.
Thread Starter
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From: In limbo
St. Jude Donor '13-'15, '17 thru '22
Be absolutely sure the "ground" wire actually is a ground. Frame ground for the wiper motor originates from the starter... It is black, but so is the hot wire from the battery to the starter. I've seen many instances where someone replaces the starter and connects all black wires to the "hot" terminal.. Check it out.
Just an idea..
Just an idea..
I am pretty sure that is the TCS relay. It was listed on one of my wiring diagrams (in the AIM), but not the other two. It shouldn't affect the wiper system at all, but I will try unplugging it and running my wipers later today.
Also, JimT makes a good suggestion. Make sure that the motor ground is actually grounded and that the yellow and red wires to the motor have 12V when the car is on (engine can be off) and the wiper door is up.
Also, JimT makes a good suggestion. Make sure that the motor ground is actually grounded and that the yellow and red wires to the motor have 12V when the car is on (engine can be off) and the wiper door is up.
I just tested to see if the relay clicks when the switch is thrown. I connected the battery (have been leaving it disconnected due to shorting problems that I think I am past), put the key in run, car definitely has power (courtesy lights came on, clock started running), wiper door is open, I could not hear a click of the solenoid when turning the switch to slow. I have tested the relay based on Willcox videos (as well as the motor and switch), and it tests as good. Any help there is greatly appreciated.
Instructor
Joined: Jun 2015
Posts: 212
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From: State College Pennsylvania
I will re-check the ground tonight. So if I read the above correctly, the wire to the ground on the wiper motor should be a black wire (no stripe), and should go from the wiper motor to the starter?
I just tested to see if the relay clicks when the switch is thrown. I connected the battery (have been leaving it disconnected due to shorting problems that I think I am past), put the key in run, car definitely has power (courtesy lights came on, clock started running), wiper door is open, I could not hear a click of the solenoid when turning the switch to slow. I have tested the relay based on Willcox videos (as well as the motor and switch), and it tests as good. Any help there is greatly appreciated.
I just tested to see if the relay clicks when the switch is thrown. I connected the battery (have been leaving it disconnected due to shorting problems that I think I am past), put the key in run, car definitely has power (courtesy lights came on, clock started running), wiper door is open, I could not hear a click of the solenoid when turning the switch to slow. I have tested the relay based on Willcox videos (as well as the motor and switch), and it tests as good. Any help there is greatly appreciated.
The wiper relay not clicking is usually a symptom of a bad switch ground. If your gauge bezel is broken like many others, you will need to run a separate ground wire to the switch. The beginning of this thread illustrates this well: https://www.corvetteforum.com/forums...-question.html
The wiper motor won't do anything until this relay works, so that should be done first.
Thread Starter
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St. Jude Donor '13-'15, '17 thru '22
Yes, the wiper ground was originally a black wire, but I think it was connected to the blower ground (which is then connected to the starter ground). I've ran my own ground wire to the alternator for testing purposes when I was having trouble.
The wiper relay not clicking is usually a symptom of a bad switch ground. If your gauge bezel is broken like many others, you will need to run a separate ground wire to the switch. The beginning of this thread illustrates this well: https://www.corvetteforum.com/forums...-question.html
The wiper motor won't do anything until this relay works, so that should be done first.
The wiper relay not clicking is usually a symptom of a bad switch ground. If your gauge bezel is broken like many others, you will need to run a separate ground wire to the switch. The beginning of this thread illustrates this well: https://www.corvetteforum.com/forums...-question.html
The wiper motor won't do anything until this relay works, so that should be done first.
First, tonight's homework completed:
Ground: Reconnected as in my post #29. The plain black wire definitely tests as ground (less than 0.1 ohm to the negative connection at the battery). Full battery voltage at the yellow and red wires.
I will check the switch ground now.
Thanks!
PK