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Need more electrical help, PLEASE!

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Old Sep 2, 2016 | 08:32 PM
  #21  
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St. Jude Donor '13-'15, '17 thru '22
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I think this is a case of a picture is worth a thousand words. Here is one:



It is easy to see a black wire coming from the area of the yellow-green-blue connection that is not connected (it has a red splice in it). This wire tests no voltage to ground, and less than 1 ohm of resistance to ground. Further down in the picture, there is a brown wire coming out of the body of the wiper motor with a stripped end, also not connected to anything. This wire tests hot (12.8 volts potential difference to ground) even with the ignition switch off, and the key removed. At one point, these two were connected, creating a short that drained my battery, so I feel that mystery is solved.

However, I still can't figure out to what those wires should be connected? Also, the Willcox diagrams show a 5 pin wiper relay, and it appears that my relay is only 3 pin.

any guidance here is greatly appreciated!

Last edited by Derrick Reynolds; Sep 2, 2016 at 08:34 PM.
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Old Sep 3, 2016 | 04:41 PM
  #22  
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Originally Posted by Alan 71
Hi PK,
I believe this ground connection at a starter bolt is part of the wiper motor circuit.
Have you checked it?
Regards,
Alan

Alan:

Sorry I missed this, and thanks for the reply. That ground is part of the ignition harness that I replaced last year. It is there, and brand new looking like yours!

Upon further inspection, there are two wires coming out of the body of the wiper motor. One goes into the head of the wiper motor next to the 3 way connector, visible in the picture. I believe this is a ground wire that is supposed to be there, but it looks like some Bubba spliced another connection into it, which is the wire we see floating in the picture. The other wire coming out of the body is more brownish, has voltage all the time, and I can't figure out where it goes from the diagrams above.

On your wiper relay, how many terminals do you have? Mine has 3, and looks old as the hills (visible in the phot) so I suspect original.
The diagram from Willcox seems to show a 5 terminal relay.

Any and all help is appreciated. FWIW, I started replacing wiring harnesses because Bubba has been hard at work on my electrical system over the decades. I take nothing I see on my car to be "correct". My fears were well-founded on the blower motor problem, as the issue was caused by an incorrect 4 terminal relay being installed, when a 5 terminal one was correct.
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Old Sep 3, 2016 | 04:50 PM
  #23  
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Originally Posted by 7T1vette
Something in the system is creating a dead-short. And I suspect that it is in the wiper motor. When the motor was not connected, your blower motor worked. Add in the wipers and shorts abound.
Correct. I had some wires connected incorrectly, and found a low-amperage short. This is what killed my battery over the course of a few days. I don't see any more shorts, but having 2 blower motor fuses blow in the last year has me keeping my eyes open.

Remove the connections from the wiper motor and then there should be some kind of testing that you can do between terminals on them to see if all is OK. I don't have that info, but think that testing with an ohmmeter to see what resistances you have between all combinations of the terminals should help you decide if there is a short in the motor assembly (as I suspect).
I think I did this, but I wouldn't be surprised if I got it wrong. The yellow wire is hot whenever the wiper switch is on. The green and blue wires never get voltage, and are grounds of differing resistance. I think this is correct for these three wires. I tested the two coming from the body of the motor, one is hot, the other ground. I am not sure where these need to get connected.

If you have blown one (or more) fusible links, you should know that you should NOT replace them with regular wire. You should find suitable fusible links to replace them. Yes, they are just smaller AWG wire...but they are inside non-flammable insulation and terminated by non-flammable end pieces. That way, if there is a short that fries the fusible link, the insulation will not catch fire.
No fusible links blown . . . .yet. One of the reasons I decided to replace two wiring harnesses is that they old ones were Bubbatized greatly. One of the wires that should have had a fusible link, didn't have one. It does now.

Thanks for the help. Maybe with the additional information above, we can figure out where my wires need to go!
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Old Sep 9, 2016 | 02:03 PM
  #24  
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I want to bump this back up. Can someone PLEASE look at their '70 or thereabouts car and tell me where the two wires coming from the body of the wiper motor go? I can't seem to figure it out looking at the diagrams.

Thanks.
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Old Sep 30, 2016 | 06:56 PM
  #25  
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No help? Really? Would an offer of a beer get someone to take a pic?
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Old Sep 30, 2016 | 07:51 PM
  #26  
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Sorry I canrt help, ive got a 68. Did you try doc rebuilds ez wiring diagrams. Or wilcox?
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