It has been about 10 months that I have been working on this off and on. I am going to give it one more shot, and if I don't get them working this time, I'll have to put the car back together and take it to a professional.

History: 1970 BB AC, when I bought it, the blower motor would blow the fuse after a few minutes of use. Attempts to fix it caused me to realize that the wiring harness had been Bubba's a half a dozen times or more, so I replaced it.

Upon replacing the harness, the wipers no longer worked.

The motor, switch, and relay have been tested per the Willcox technical help, and all tested fine (not surprising, since they all worked before the change of the harness.

What I think the problem is: There are two wires coming out of the wiper motor itself. The black wire, and the black wire with a purple stripe. The black wire was cut and spliced when I got the car (making me think Bubba was down this same road years ago), and the splice came undone when the harness was changed. Now, the side that comes out of the motor always has voltage. From reading the Willcox tech help, this is correct. Let me know if I have this wrong. However, the other side tests straight to ground. So, re-connecting this wire is a dead short, and kills the battery without the wipers ever running. Any ideas?

 

There should be a red wire coming from the limit switch and running to the wiper motor connector. This wire should have power at all times.

Then you'd have the 123 connector with power in the middle and the ground wires and then there should be a black ground wire to the case that is on the same grounding circuit as the blower motor.

Willcox

 

What is the "limit switch"? I'm not sure what that is.

Yes, I have power at #2 (yellow wire), and ground (with varying resistance) at #1 and #3 (light green and light blue respectively).

 

There is a limit switch mounted to the firewall and the plunger from the wiper door linkage will collapse it when the door is closed. When it's in the open position power will travel through this switch to the motor.

Limit switch.


Wiper motor limit switch connector.

 

I never have problems with my wiper door on my 77.

 

Yes, I see it, red with a white stripe wire (sorry for the confusion with a red wire). The door is open, and there is battery voltage at the connector. Thanks.

But as I stated above, I know the motor has power, it just is shorted out. The black wire that is cut is the power wire to the wiper motor, and the one side has power at all times at the moment. I now understand that this is only because the wiper door is open. But the other side of the cut wire has only 1.4 ohms resistance to ground. Connecting them is a short. Any ideas why?

 

There is no black wire to the motor in the engine compartment side and only one at the relay which is a ground. (Aside from the black ground that plugs into the lug on the front of the washer pump) cover. ????

Power comes to the limit switch from the over-ride switch in the dash. This power then goes through the limit switch and where the opposite end of the red/white limit switch connector plugs in is where you plug in your wiper motor red wire (should be sticking out the bottom of the motor). This is what supplies power to the motor as well as the yellow wire on the 123 connector (number 2). The yellow wire splits off and powers the washer pump along with a light blue wire which is a ground. The other outer wires at the 123 are grounds as well... that just leaves the black ground to the blower motor.

Test the one wire and see if it pings to the blower motor ground. Report back.. I won't be on until sometime tomorrow.

Willcox

 

I'm sorry, but I totally don't get this. I admit that when working on cars, electrical stuff is my WEAKEST area, so forgive me if I am being dense. I am also unbelievably grateful for all the help you have given me, as well as all the time you have put into the technical help on your website!

That said, for example, I am looking here:

http://repairs.willcoxcorvette.com/1...d-wiper-motor/

There are two wires coming out of the body of the wiper motor, one is black, the other is black with a purple stripe. In the photo, the black with a purple stripe wire appears to come out of the wiper motor, and attach to a tab that is connected to connection #4. This is how it appears in my car as well. The black wire appears to come out of the wiper motor, and connect to the #2 terminal in the 123 connector. This is also how it appears in my car. HOWEVER, in my car, the black wire that connects from the body of the wiper motor to the #2 connection of the 123 connector is cut, and the side toward the wiper motor always has voltage, where the side toward the 123 connector has no resistance to ground. This is what causes the short.

I can try to take pictures if that helps.

Thanks!

PK

 

Are those two wires cut? Those wires go to the terminal board and to the park switch but are not external to the motor...

There should be three wires that plug into the 123 connector, green, yellow and blue.

Then there should be a red wire running out of the bottom that plugs into the limit switch circuit and a black ground. If the internal wires on the motor have been cut... you'll need to either re-attach them or get another motor.

You can see the internal wire and where they go in the picture below.

 

I'm not sure I understand this either, but if you are talking about the 2 red wires running horizontally across the picture, I don't know. The motor is still installed in the car, so I can't see any of the internal wires. Do I need to pull the motor out of the car?

The two wires I am talking about are visible at the top of the picture in your post, coming out from under the blue tape. One of them is black, the other is black with a purple stripe. The black one of these is cut, and the side toward the wiper motor body tests with full battery voltage. The other side of the cut shows ground. Re-connecting these wires causes a short.

Those wires are there, and working (as far as I know) as they should based on your troubleshooting guides.

Let me know if pictures would help. I have some, and can take more if it helps.

 

Pictures would definitely help.

 

Let me know what pictures would help, and I will gladly provide. Like I said, the wire that is cut and causing the short is clearly visible in your photo in post #9, coming out from under the blue tape.

I can't believe any of the internal wires are cut or not functional since the wiper motor ran before the wiring harness was changed, and has even moved a few times with my experimentation (which is why the wiper door is open).

 

 

In the pic above, you can see the body of the wiper motor center screen. You can see the two wires coming out of the body of the wiper motor, one black, the other black with a blue-looking stripe (although I know the wiring diagram shows purple stripe). I purposely put the piece of paper there to show that the black wire is cut, with the two ends of the cut clearly visible.

The exposed end lower in the picture always has battery voltage, and the end higher in the picture (clearly connected to a red crimp connector) tests full continuity to ground.

Let me know if there is any way I can show this more clearly.

Thanks,

PK

 

pull the motor and do a bench test per Wilcox's tutorial. it is possible you have the wrong motor, and/or it is wired incorrectly.

read this thread
https://www.corvetteforum.com/forums...-assembly.html

 

I have to agree... It's possible the motor is the wrong one... but if you pull it and picture it up for me I can ID it and tell you.

If it is the wrong motor this might explain some things. It's too easy to pull, you remove the three nuts that retain the motor to the firewall and then remove the bell crank nut.

Willcox

 

You know, at this point, it makes sense. Worst case is I can fix that cut wire better than the jury rig that is in there right now, and confirm that another component is correct. Since it sounds easy, I will try to do it tonight, but I won't be around all day tomorrow.

Thanks!

 

Wiper motor is out. Pic:

 

Picture of the other side:

 

Last pic for tonight:



If the writing on the stamp is not clear enough, it says:

DELCO PRODUCTS
DAYTON, OH
MADE IN U.S.A.
4918077

Further guidance is appreciated!

Edited to add: Clear enough or not, it's friggin' upside down! Frickin' iPhone!