windshield washer pump

bedwards

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1985 C10. My washer pump died today. Pump motors not getting 12v. It works on the bench. Checked fuses and wiring. I didn't see a fuse for the pump. The wipers work fine, even the intermittent speeds. What am I missing or has the multi-function switch died? Any easy way to check?

many thanks ahead
 

Snoots

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Apparently, You've checked the voltage, how about checking continuity from the switch?
 

bedwards

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I guess that's next. Where, under the steering column where the all the wiring connectors are on the right side?
 

bedwards

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Success!!!!
So the washer as well as all wiper functions go through that POS delay module. I had a hunch as mine has been acting up for a while. It would wipe three times when I start the truck sometimes and then the washer pump quit getting 12v.
I will try to post pics but basically there is a diode on the module board that fried on mine. It fell apart when I tried to take it off the board. I happened to have one in a box of junk I got from my dad who is a retired EE.

Many thanks to "bucket" who posted his module and schematic! https://www.gmsquarebody.com/threads/wiper-pulse-module-15598496.28952/

The part was a 1N4002. Replaced it and all functions are back.
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Corvette Ed

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calredneck

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Is any buddy rebuilding these I will pay
 

Raider L

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@bedwards,

This is what's in your truck, to run your washer pump and wipers???? You gotta' be kiddin"? Is this thing located under the dash somewhere? You gotta' be kiddin'?? Did GM try to see if they could make it as complicated as they could just operate that old washer, and same wiper motor that's been in Squares forever?
 

SirRobyn0

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@bedwards,

This is what's in your truck, to run your washer pump and wipers???? You gotta' be kiddin"? Is this thing located under the dash somewhere? You gotta' be kiddin'?? Did GM try to see if they could make it as complicated as they could just operate that old washer, and same wiper motor that's been in Squares forever?
This was very common in the 80's not just for GM, but Chrysler did it to, can't remember if Ford did, it was for the delay. So they started out using the same wiper motors, but a switch with the delay function. In order to make the same old wiper motor perform the functions of delay they added a delay module box and ran everything for the wipers though it. Later on the motors were changed and used a different part number for delay, but the separate delay box continued on until sometime in the 90's I think. They are terribly obsolete now.

@calredneck If no one on the forum wants to rebuild it for you, at the shop we have used a company called AES modules out of Jacksonville, FL.
 

calredneck

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Thank you Raider L
 

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