# Chevy Volt / Opel Ampera 3-way valve



## oudevolvo (Mar 10, 2015)

As a radiator bypass valve I'd like to try to use a 3-way valve from a Chevy Volt.
Part = 22830923
Has anyone else used it?
I've got two main questions:
- Is the electrical connector available somewhere (it's a six pin)?
- What is the pinout for controlling it?








Hope someone already figured this out.
Otherwise it will be trial and error (with not too much error I hope)


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## swoozle (Nov 13, 2011)

There's a lot of info in the Ampera service manual that is floating around. I was interested in that valve as well so I pulled the relevant pages out. Attached.


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## arber333 (Dec 13, 2010)

swoozle said:


> There's a lot of info in the Ampera service manual that is floating around. I was interested in that valve as well so I pulled the relevant pages out. Attached.


Nice excerpt, i see it uses a 12V as working voltage and 5V for control signal.

I am not sure what kind of signal is required. I would try PWM 1kHz and vary....


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## swoozle (Nov 13, 2011)

arber333 said:


> Nice excerpt, i see it uses a 12V as working voltage and 5V for control signal.
> 
> I am not sure what kind of signal is required. I would try PWM 1kHz and vary....


Only very tenuously related, but the Tesla coolant pump I'm using wants a 2 Hz PWM control signal. Maybe there's some benefit to very low PWM frequencies for these low speed control requirements.


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## swoozle (Nov 13, 2011)

This is interesting:
https://www.tlxtech.com/understanding-solenoids/theory-operation/pwm-solenoid-theory

It talks about PWM for position control solenoid valves (which this sounds like) using a PWM frequency "typically in the range of 200 to 1000 Hz."


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## swoozle (Nov 13, 2011)

I'm pretty certain I'll need one of these so I just bought one off of ebay. Let me know what you figure out.


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## oudevolvo (Mar 10, 2015)

Thanks @Swoozle did not expect the input would be that perfect!
I'm quite sure I would not have been able to figure that out by trail and error.

I used my Arduino Mega and a PWM frequency of 980 Hz building on the recommendations and it works like a charm!
Duty cycle 75% = link position = flow from top to bottom outlet and 3,3V on sensor signal pin (#4)
Duty cycle 25% = bypass position = flow from top to right outlet and 2V on sensor signal pin (#4)
Top/bottom/right as per attached photo.


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## arber333 (Dec 13, 2010)

oudevolvo said:


> Thanks @Swoozle did not expect the input would be that perfect!
> I'm quite sure I would not have been able to figure that out by trail and error.
> 
> I used my Arduino Mega and a PWM frequency of 980 Hz building on the recommendations and it works like a charm!
> ...



Thank you for the feedback. 

I also found that Ampera/Volt GM coolant pumps work with 1kHz signal while varying duty from 55% to 75%. If applied less than 55% it wont move and more than 75% it dies out after a short time.


Front coolant fan though needs reversed pwm signal. 1kHz still applies, however 95% power happens at cca 20% duty. 30% power works then at some 80% duty.
I think it is worth to use such a system since those BLDC fans are very efficient. At 20% power they both use only 6A!


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## oudevolvo (Mar 10, 2015)

And then the question is: can we also get the 4-way to operate?
I have made a similar excerpt from the service manual.
Is not as clear and straightforward as the 3-way one..
View attachment Battery Valve Service_Manual Chevy Volt.pdf


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## oudevolvo (Mar 10, 2015)

The 4-way valve also has a six pin connector of which only 5 are used.
1= Motor High Control
2= Motor Low Control
3= not used
4 = Sensor Signal
5 = Low Reference
6 = Sensor High Reference
From the schematic I understand 6 = 5V and 5 = ground
I assume pin 4 is the same as the 3-way valve accepting 25% and 75% duty cycle
An then 
1 = 12V + 2 = ground is one way 
and 
2 = 12V and 1 = ground is the other way
Do you interpret the same from the documentation?


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## oudevolvo (Mar 10, 2015)

Well. the fact that also for the 4-way valve pin #4 was the signal pin was wishful thinking. I got myself a 4-way as well and got it to work
- pin 3 = unused
- pin 4 = feedback for position
- pin 5 = GND
- pin 6 = 5V

In case
pin 1 = 12V and pin 2 = ground, the valve goes to the Chiller position and the feedback pin gives 1,84V (after disconnecting 12v)

pin 2= 12V and pin 1 = ground, the valve goes to the Radiator position and the feedback pin gives 3,24V (after disconnecting 12v)

If you want the valve to be in the bypass position, you need to apply 12 volt and at a certain point. Then (with 12V disconnected) the feedback is 2,54 V

I'm not sure whether the valve likes or needs 12V. When I feed pin 1_2 with a 1.5V penlite battery it moves as well and much slower.

See attached photo for outlet references.


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## oudevolvo (Mar 10, 2015)

Next question is, which one do you recommend using in my project? I see pros and cons for both:
3-way 
pro = easier to control and less hoses
con = less ideal flow in non-radiator circumstances
4- way
pro = better flow when radiator not in use
con = more difficult to control and more crowded in terms of hoses

*3-Way*
Pump gets fed either via radiator or heater (might be on or not). 







And this is how it would bolt in.







Disadvantage, the bypass and heater flow goes over the motor since the heater will be on the left hand side of the motor.








*4-way*
The flow will only go over the motor when it's needed for heating. Otherwise it will just bypass the radiator and get fed directly from the catch tank.







And I can position the valve like this.








Looking forward to hearing your thoughts.


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## swoozle (Nov 13, 2011)

In my view simple is good. I'm using the 3-way because my heater is installed in the main coolant line right after the pump. There's no disadvantage, at least with the Volt heaters; if they aren't on they don't affect anything. The valve will merely shunt coolant (or not) off to the radiator right before the catch tank.

I doubt there will be any significant effect in your less-ideal-flow scenario. Most of your flow resistance will be in the batteries and radiator, not the lengths of unrestricted coolant hose.


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## oudevolvo (Mar 10, 2015)

swoozle said:


> In my view simple is good.


Thanks!
A night sleep made me conclude the same.
3-way it is!


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