PWM for fans, will this work?

[rickpaw]

Originally Posted by Larry R

Same topic, new issue. My A/C was not performing up to what I thought it should and since I am short of time I took it to a reliable A/C man. He checked everything over and discovered it was slightly over charged and took care of that. He also noticed the compressor laboring and decided to unplug the jack to my A/C transducer which is in my PWM circuit. Immediately the fans sped up and soon the A/C was performing as it should be. This is good, but I am trying to understand why the fans would go to full or near full RPM when the transducer was unplugged. I tried this at home with the same results. I can and will change some of the parameters in the input/output PWM page of my HP ECU to get the fans to come on sooner, but would like to understand why the above happened. Any input will be appreciated. Larry

Bringing this back up to the top, as I started playing with the ECU (Dominator) programming.

Larry, is it possible that the values for the transducer is a bit off? So the ECU is reading the pressure lower that it actually is?

[andrewb70]

Originally Posted by rickpaw

Bringing this back up to the top, as I started playing with the ECU (Dominator) programming.

Larry, is it possible that the values for the transducer is a bit off? So the ECU is reading the pressure lower that it actually is?

I'm sure Larry will chime in, but as I recall, he ended up having some wiring issues, which I helped him resolve, and it's all working as it should now.

Andrew

[rickpaw]

Thanks Andrew. It would be nice to know what kind of wiring issues Larry was having.