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Controlling ES27C AC Compressors?

1745 Views 1 Reply 2 Participants Last post by  Marcio
Good day everyone,

I've been trying to research high and low to try and figure this out, but I'm stumped. I picked up an ES27C air conditioning compressor with hopes to use it in my project, but I did not think the information regarding this compressor would be so hard to come by considering how easy it is to get one.

It has an internal inverter, which it would only make sense to take advantage of, but I cant seem to get it to turn on. I know it uses some kind of information fed to it. I found articles of guys using the larger ES34 compressors from Tesla's and controlling them with a PWM signal, but either something is up with my setup or the ES27 is not controlled the same way. it does have only 6 pins for control, not 7 like the 34 does.

I have a ~260V supply connected to it, which should be well within its operating rage of 144-488v. At the moment I am just trying to get it running on the bench before I mount it in-car.

What I have deduced so far is this:

On the 6-pin connector:
Pin 1 - Clock-- My compressor is outputting a clock signal here, which seems odd

Pin 2 - "ITE" / "D In"-- I presume this is the input to the compressor

Pin 3 - "ETI" / "D Out"-- As such, I presume this is data back from the compressor regarding errors.

Pin 4 - "STB". All applications I found of this compressor pull this pin low.

Pin 5 - Ground

Pin 6 - 12v ignition power

Looking at what information I could find on google and on AllData, ITE and ETI may provide a similar signal, although I have seen instances where no data was reported on the ETI line. I would imagine this line may not be totally important here anyhow.

The compressor I got came from an 08 Camry, but I know some Altima hybrids use the same one as well. They have different pin names on some wires, but the control signals seem to be the same.

So I am kind of at a loss here, I tried feeding it a PWM signal of varying duty cycles and that didn't make it tick, so I'm guessing I'm not feeding it the right information. I haven't got a Camry/Prius/Altima or the sort at my disposal to scan the signals from, but I may have to find something.

So, I'm hoping someone somewhere has figured something out. I thank you all in advance.
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