HVAC Blend Door Actuator motor test

[sdancer75]

Hi,

This HVAC blend door motor actuator was removed from a Volvo car. It's responsible for changing the damper from heat to cold and vice versa. It has 3 pins.

1 pin red = voltage
2 pin purple = frequency
3 pin black = ground.

How can I test this motor on my bench with external PSU? The problem here is the frequency. How can I feed a frequency to rotate the motor?

[amyk]

That's actually a Ford part, but you'll probably need a signal generator to produce the right (PWM?) signal; likely similar to https://en.wikipedia.org/wiki/Servo_control .

[sdancer75]

Thanks for the reply. I just want to make sure it works fine, unfortunately, I don't have a function generator. Can I try using a custom FG using ie Arduino PWM? Will this work?

1pin = 12V supply
2 pin = PWM
3 pin = GND

[sdancer75]

I finally opened the box. It seems that has a motor controlled from an IC named ELMOS 14301B. No datasheet found. Any infos about this? Does this motor controller is uniquely programmed to be used only for the mached VIM? How this motor is working and how can I test it?

[sdancer75]

Extra Photos

[sdancer75]

Photos...

[sdancer75]

I made a first unsuccessful try.

With external power supply I connected 12V to Red line and Ground to black line. Using my GM328 tester, I connected the purple (pin2) line with the PWM output of the GM328.

I verified with my DMM the duty cycle of the GM328 output but nothing, the motor didn't move. The grounds from the PSU and GM328 were connected to create a common ground.

Any other ideas?

[Dan N]

You didn't give the year, but this old article from 2000 describes the different types of actuators and how they are controlled:
https://www.motor.com/magazine-summary/diagnosing-electronic-climate-control-actuators-april-2000/

Most likely the third wire is a sensor output.