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Discussion Starter · #1 ·
When I started having problems with the windshield washer (front and rear windows), I thought it might be due to making my own washer fluid (sometimes you have to be creative when Walmart is always out of fluid). I disconnected lines, blew air through them to make sure I had no clogged lines, yet kept having problems. My car lived in the San Francisco Bay Area for all but the last 5 months, where I have been living in the Austin TX area ever since.

I checked the fuse when I stopped hearing the washer fluid pump actuate when pressing the washer stalk forwards or back. No blown fuse. Washer fluid tank was full. Ended up taking the car to the dealership.

They played around with the car a while, and then announced they had to replace the washer fluid pump (mileage on car = 11300 miles). Surely this would end the problem.
I got in the car, gave the front windshield a quick squirt to confirm success, and headed down the road..

After a few miles, I decided to give both the front and rear windows a good wash. Actuated the washer fluid pump... NOTHING. No sound, no fluid. I went home, verified the washer fluid reservoir was still full, and went back to the dealership.

They tinkered with the car some more, and then came up with the claim that the washer fluid motor stressed the fuse, partially blowing it. Changing the motor, according to their wisdom, caused the fuse to blow fully. They said that if the fuse blows again, there must be something wrong with the car's wiring.

Sure enough, the fuse failed again. Anyone else have problems with the 10 Amp circuit powering the windshield washer fluid pump? Seems like a bizarre problem, perhaps not...
 

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The dealers story, without knowing more details, sounds like malarky. You need to see if they can pull a DTC (diagnostic trouble code) for a short in the washer motor and hopefully this includes the wiring. The washer motor is controlled by the BCM or body control module, a mini computer that works all the lights, windows and other non-critical functions. They can hopefully pull a trouble code from it. Maybe a mouse chewed through a wire, who knows? There is no such thing as partially blowing a mini-fuse such as in this circuit. It is all or nothing. Hope you are not paying for this.




DTC B371A 39

Windshield Wiper Motor Internal Malfunction

Circuit/System Description

B+ voltage and ground are supplied to the windshield wiper motor. Whenever the vehice is ON or in Service Mode, the body control module (BCM) sends the wiper/washer switch status through the LIN communication bus. If a fault occurs at any time in the windshield wiper motor, the BCM will set the DTC.

Conditions for Running the DTC

The BCM runs the diagnostic to detect an internal fault when power up is commanded. The only requirements are voltage and ground. This diagnostic runs even if the voltage is out of the valid operating range.





Conditions for Setting the DTC

The BCM receives an invalid signal from the windshield wiper motor.

Action Taken When the DTC Sets

The BCM ignores all additional inputs.

Conditions for Clearing the DTC

A current DTC clears when the diagnostic runs and passes.

Reference Information

Schematic Reference

Wiper/Washer Schematics

Connector End View Reference

COMPONENT CONNECTOR END VIEWS -INDEX

Description and Operation

Wiper/Washer System Description and Operation

Electrical Information Reference

Circuit Testing Connector Repairs



/









Testing for Intermittent Conditions and Poor Connections Wiring Repairs

Scan Tool Reference
Control Module References for scan tool information Circuit/System Verification

1. Vehicle in Service Mode.
2. Verify that there is no communications DTC set.

If there is a communications DTC set

Refer to Diagnostic Trouble Code (DTC) List - Vehicle .

If there is no communications DTC set

3. Verify that DTC B371A is not set.

If DTC B371A is set

Replace the M75 Windshield Wiper Motor.

If DTC B371A is not set

4. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
 

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I thought it might be due to making my own washer fluid (sometimes you have to be creative when Walmart is always out of fluid).
...How exactly did you make your own washer fluid? Even if the lines are free from obstruction, the nozzles and/or inside the pump, may not be completely clear and undamaged from your "homebrew." Obstructions=More Power to Overcome=Blown Fuses=No Washy Washy. Whatever you do, DO NOT REPLACE WITH A FUSE WITH A GREATER AMP RATING. There have been plenty of Bolt fires recently, no need to add to the list.

If it were me: I'd drain/siphon the homebrew, refill with commercial/legitimate wiper fluid; check the outbound power supply contact at the fuse for ground continuity with the pumps unplugged; if no ground continuity exists, I would then use the exact specified fuse and try my front wipers for 10 seconds; regardless of front wiper success, I would then try the rear for 10 seconds, even if I had to replace a blown fuse, again with the exact rating specified.

Good luck. I hope this doesn't end up being the shirt show I'm envisioning.
 

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(sometimes you have to be creative when Walmart is always out of fluid)
Oh, and on this point, regarding fluids in your vehicle, only in a dire emergency should you ever consider putting "creative" or anything other than specified fluids into your vehicle. If this isn't being covered under warranty, you're probably in the midst of learning this the hard/financial way.
 

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Sorry, I pasted a code for the wiper motor, not the washer pump. I doubt there is a code for the washer pump but who knows? I will see if there is one but it too late tonight. Good point above about the viscosity of your homemade fluid. What did you make it out of? Should be no thicker than water.
 

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Discussion Starter · #7 ·
...How exactly did you make your own washer fluid? Even if the lines are free from obstruction, the nozzles and/or inside the pump, may not be completely clear and undamaged from your "homebrew." Obstructions=More Power to Overcome=Blown Fuses=No Washy Washy. Whatever you do, DO NOT REPLACE WITH A FUSE WITH A GREATER AMP RATING. There have been plenty of Bolt fires recently, no need to add to the list.

If it were me: I'd drain/siphon the homebrew, refill with commercial/legitimate wiper fluid; check the outbound power supply contact at the fuse for ground continuity with the pumps unplugged; if no ground continuity exists, I would then use the exact specified fuse and try my front wipers for 10 seconds; regardless of front wiper success, I would then try the rear for 10 seconds, even if I had to replace a blown fuse, again with the exact rating specified.

Good luck. I hope this doesn't end up being the shirt show I'm envisioning.
I use a mixture of vinegar and water, plus 10% rubbing alcohol to the mix for the washer fluid. The alcohol prevents anything growing in the fluid, and it works like a charm. Basically followed one of the formulas from How to Make Your Own Windshield Washer Fluid - no worries, I have no intention of allowing anyone to put anything but the stock recommended 10 Amp fuse into the circuit.
 

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....the BCM does control the washer pump but the troubleshooting is many pages long. Here is the first page, maybe you can take it to the dealer and ask them if they are following the book. I guess after you verify the fluid is not the problem. Doesn't sound like it should be based on your mixture, but I'm not sure alcohol is good for car paint.
Anyway, the trouble codes are B3873 01 02, and 04. When they repair or replace the pump they are suppose to clear the code and then test the pump and see if a code reappears.
Of course in your case the pump just stops so it is pretty obvious. It may not be the pump but something upstream to it.

DTC B3873

Front Washer Relay Circuit
For symptom byte information, refer to Symptom Byte List . Diagnostic Fault Information

Circuit/System Description

The windshield washer pump is controlled by the body control module (BCM) via a printed circuit board (PCB) relay. When the washer switch is depressed, the BCM's internally pulled high resistor is pulled low by the washer request circuit. The BCM then applies voltage through a control circuit to the PCB windshield washer pump relay. With the relay energized, fused battery voltage is applied through the switch contacts of the relay and the control circuit to activate the windshield washer fluid pump.

Conditions for Running the DTC

Vehicle ON or in Service Mode
The system voltage is between 9 - 16 V.

Conditions for Setting the DTC

B3873 01

The body control module detects a short to B+ in the windshield washer pump relay control circuit

B3873 02

The body control module detects a short to ground in the windshield washer pump relay control circuit

B3873 04

The body control module detects an open or high resistance in the windshield washer pump relay control circuit

Action Taken When the DTC Sets

Washer operation is suspended.

Conditions for Clearing the DTC

A current DTC clears when the diagnostic runs and passes.
 

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I've used distilled water and vinegar in a pinch, but never use tap water. And if you are going to use distilled, that's 59 to 99 cents and at that point, washer fluid isn't much more. :)

Mike
 

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Don't know if you've noticed/read other threads here re: mice & vermin eating the wires under the hood in Bolts (and in other newer cars using soy-based insulation). You may want to look around under your hood for damaged wires?
 

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Discussion Starter · #12 ·
Don't know if you've noticed/read other threads here re: mice & vermin eating the wires under the hood in Bolts (and in other newer cars using soy-based insulation). You may want to look around under your hood for damaged wires?
I have checked for vermin. No signs of damage, and the car has been stored in a garage that is sealed from pests with no evidence of any pests getting in to cause damage.
 

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Discussion Starter · #13 ·
I've used distilled water and vinegar in a pinch, but never use tap water. And if you are going to use distilled, that's 59 to 99 cents and at that point, washer fluid isn't much more. :)

Mike
I've used distilled water and vinegar in a pinch, but never use tap water. And if you are going to use distilled, that's 59 to 99 cents and at that point, washer fluid isn't much more. :)

Mike
Thanks for the suggestion. I unfortunately do not want to pull apart the car to drain the tank, and without a working washer fluid pump I have no way to drain the tank and replace it with any other fluid.
 

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Thanks for the suggestion. I unfortunately do not want to pull apart the car to drain the tank, and without a working washer fluid pump I have no way to drain the tank and replace it with any other fluid.
You don't have to pull anything apart to drain the vast majority of the tank. For a couple bucks of thin hose from the hardware store, fitted to a pumper from a soap or lotion bottle, and 20 minutes of time, should probably be sufficient to rid the reservoir of the home brew.
I have no first-hand knowledge, but according to the internet, vinegar and rubber don't get along very well, leading to the degradation of rubber. If the dealer discovers your "replacement wiper fluid" is the cause of the problem, if it was being covered under warranty originally, don't be surprised when they do an about-face and hit you with the bill (don't be too upset, they'll probably figure out a way to charge GM too). If your mixture has damaged the hose lining, this will likely be a continual problem, unless all of the hose is replaced (yes that includes the entire run to the rear window).
 

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Vinegar is acidic, I have seen reports of folks damaging washing machines and dishwashers using vinegar to clean them. I would be very suspicious that the washer pump submerged in vinegar could be your issue

 

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Exact same thing here as OP. Cannot activate windshield wiper fluid. I also just added fresh fluid 2 days ago ..was working then. Just standard wiper fluid (winter blend to 25 below)

Is there a fuse just for the fluid?

Also wanted to disconnect 12v and do a reset ..is it ok to leave the charger plugged in ?

OP any chance you had really cold weather lately ? we've been below freezing ...just throwing that out for consideration...
 

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so what would fry...me or the car
I'd be most concerned with HV arching on contactors with abrupt 12v removal, but other errors might occur as well. If you end up arching your contractor closed on your EVSE, then touch a HV contact on the plug, the result might SHOCK you or kill you.
 
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