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Washer fluid setting shorting out wiper system

I bought my Saturn in January. The wipers and fluid system worked fine at first. Around July, car was overheating to the point that relays were hot to hand hover (not even touching them yet). I fixed the overheating (bad cooling fan relays) and changed the general wiper system relay (same relay as the cooling fans) but didn’t change relay for the “front wiper” (different from the three before). Well, I started having an issue where the general wiper system fuse would blow if I tried to spray fluid on the front. I bought a large pack of the appropriate fuses to conduct experiments.
So far: I can run front wipers (all speeds), the light mist wipe setting, back wipers, and back fluid without issue. The only other setting is for spraying the front. When I try that, the fuse blows.
I have found that if I try to use the front fluid with the car turned on only to accessories, it works… fine? Sometimes it will spray in the back instead. Other times it sprays both the front and back. Sometimes nothing. I have replaced the washer pump and the wiper switch.
I cannot find a wiring diagram so I don’t know which wires to check for exposed or faulty wiring.

You said you already replaced the multifunction switch, correct? That would’ve been my first guess…

Other than that, maybe you could remove the shroud from the column and look at the wiring that goes to the multifunction switch, particularly where the column tilts.

Just throwing out ideas. Others may have a better idea through direct experience.

Try disconnecting the rear spray pump. If that solves the blown-fuse problem something may be turning both the front and rear washer pumps on at the same time and that’s overloading the circuit. Faulty washer pump(s) could be the cause too.

As far as I can tell, only one pump is used for both the front and back…

It seems a little strange that the fuse doesn’t blow out when you have the accessories on. I suspect that the fuse is also supplying power to other things besides the pump and perhaps the pump operation requires just enough current to blow out the fuse. I would invest in a factory service manual for the wiring at least and check out the circuits tied to that fuse. Ebay is a good place to find manuals for a good price. The manual will show you how things are wired together and where to find things on the car.

I presume OP means that fuse doesn’t blow if the washer pump is activated w/the key in ACC, but the engine isn’t running. The reason for that might be that the battery voltage is lower when the engine isn’t running. When the engine is running the higher voltage produces more current in the pump circuit. If the pump is on the same circuit as something else (like the windshield washer motor), the pump might be a red herring.

You make a good point about the lower battery voltage when the engine isn’t running. I have to think that turning on the pump is causing just enough extra current flow to blow out the fuse and something else on that circuit is drawing excessive current. It would be nice to know how much current is being drawn through that fuse without the pump running and what the size of the fuse is.

When I attempt a front spray, it only sprays in the back now. I thought about the non-existent rear pump… I think it’s possible the new pump is bad. Or perhaps the relay for the front wiper system is bad. I had to replace all of the relays around it as they had been ruined after an engine overheating issue. I don’t know much about electricity so this could just be poppycock. It wasn’t until I used a different relay that I got some front functionality back.
Btw, yes, all of the wiper system goes when that fuse goes. There are separate relays for the front wiper system and the back system though.

I doubt very much the pump is faulty. If the pump doesn’t work you need to check for power getting to it or apply power directly to the pump motor to verify it works correctly. I suspect that there is a problem with the wiring or the relay. If the relay has been replaced already then that should be good.

Nope. I’ll try replacing the relay and see what happens.

What year and model is your Saturn? I may be able to access a wiring diagram.

From what I’ve been able to find, the electric polarity through the single pump goes one way for front wash, and the other way for rear wash. The motor spins in either direction, and the direction determines which output gets the flow.

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That is good to know. Even my uncles thought I was crazy for believing there is only one pump.

I have a 2006 Saturn Vue 3.5L AWD.

There are two wiper/washer schematics.
Hope you can decipher them.

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Looking at the schematic it does show that the polarity to the washer motor is bidirectional. There should be 12 volts on connection pin “M” when the front washer is active. The ground side will be on pin “B” of the washer switch. Since the rear wiper works okay I would first check to see if power is getting to the front washed motor when the switch is ON. If you don’t get power at the motor then check to see if you have power if you place the common lead of the meter to a known good ground point on the chassis of the car. If you get voltage doing that, it means the ground wiring side of the circuit is open between the motor and the switch.