Weird wiper problem (not motor, pulse board or switch)

[Zacmorris]

I have a 93 1500 and the wipers only worked in the wash position. The pulsed either two, three, or four times but it did not trigger the washer motor, although the washer motor is the least of my concerns right now I’m mentioning it because it might not actually be triggering the washer setting, first I assumed it was the pulse board. Being that mine came with the old style motor, I pulled one off of a truck with a newer style motor. Same problem. Replaced the pulse board in that one with no change. Replaced the switch in the column, also with no change. The weirdest part is that in every setting except the washer position they don’t do anything, but when it’s in the high position it acts like it tries to move the wipers but then stops and smokes from the switch. So I checked for a short. The purple wire that’s supposed to run the high speed setting is showing a ground, then I used a jumper wire with it unplugged from the switch just to bump the high speed wire and it arced, just like a short to ground, if I run the same jumper to the gray low speed wire it runs in low. Also when the wiper motor itself is unplugged, it no longer is shorted and the switch doesn’t smoke. That’s what got me to try a new motor but it was the same with every motor, used or new. With the same problem happening even with a new motor, pulse board, and switch, and the wires acting like they’re shorted unless they’re unplugged, I’m at a complete loss. I would happily re-wire the circuit but every wiring diagram I’ve seen shows the purple wire being energized for high speed, but when I energize mine it’s a dead short. Does anyone have any suggestions on where to go from here?

 

[someotherguy]

When you say your 93 came with the "old style motor" that is a red flag. The motor with the easily replaceable pulse board has been in use since 1991. So, either your truck has the old style motor because someone has been dicking around with it in the past trying to solve a strange wiper problem, or is it possible you have a super-base model truck that came with non-delay wipers?

Does the lever on your column have the marks for the intermittent (delay) positions? Do you feel multiple detent positions (clicks) as you turn the switch through its range, or just a couple of speeds? You say you've replaced the switch...the actual switch inside the column, not just the turn signal lever which has no actual wiper switch function - it just controls the switch inside the column. Apologies if you already know this; you have an unusual problem here so I'm trying to get some clarification.

Richard

 

[Zacmorris]

When you say your 93 came with the "old style motor" that is a red flag. The motor with the easily replaceable pulse board has been in use since 1991. So, either your truck has the old style motor because someone has been dicking around with it in the past trying to solve a strange wiper problem, or is it possible you have a super-base model truck that came with non-delay wipers?

Does the lever on your column have the marks for the intermittent (delay) positions? Do you feel multiple detent positions (clicks) as you turn the switch through its range, or just a couple of speeds? You say you've replaced the switch...the actual switch inside the column, not just the turn signal lever which has no actual wiper switch function - it just controls the switch inside the column. Apologies if you already know this; you have an unusual problem here so I'm trying to get some clarification.

Richard

Yeah it does have the delay switch in the column, I’m assuming that’s what it came with since it does have power windows. And yes I have replaced the switch inside the column, first with a used one and the second time with a new one...all three switches gave the same results when checking resistance through the settings...the only thing really different about the truck is that I did a 5 speed conversion, so I swapped out the column, but the donor truck had delay wipers too. That and the problem was there before the swap

 

[Zacmorris]

Another odd thing that I wouldn’t think affects it too much is that the motor itself has power all the time, the switch has power with the key only but not the motor, I’m not sure if they usually do or don’t though. Just seemed odd

 

[Zacmorris]

Anyone? Does someone at least know how to wire one direct so I can eliminate the old circuit?

 

[someotherguy]

Strongly suggest using these as a troubleshooting guide instead of a re-wiring guide. Here are all 12 pages from the 1994 factory manual regarding the wipers. Sorry they're just full-resolution pictures instead of scans; my scanner doesn't take thick books and is ancient anyway. If you blow these up full-size they're totally legible and should print out decent, too.

http://www.someotherplace.com/info/DE8A91_01.JPG
http://www.someotherplace.com/info/DE8A91_02.JPG
http://www.someotherplace.com/info/DE8A91_03.JPG
http://www.someotherplace.com/info/DE8A91_04.JPG
http://www.someotherplace.com/info/DE8A91_05.JPG
http://www.someotherplace.com/info/DE8A91_06.JPG
http://www.someotherplace.com/info/DE8A91_07.JPG
http://www.someotherplace.com/info/DE8A91_08.JPG
http://www.someotherplace.com/info/DE8A91_09.JPG
http://www.someotherplace.com/info/DE8A91_10.JPG
http://www.someotherplace.com/info/DE8A91_11.JPG
http://www.someotherplace.com/info/DE8A91_12.JPG

Richard

 

[Zacmorris]

Thanks! I’ll see what I can figure out!