Thank you both for the detailed replies! I'll take all of that information into account as I configure the controls for this thing in a few weeks.

Sorry for the small print; that's the biggest image the forum software would let me upload. The +5v power supply is coming from pin 7 of the climate control unit (N22) I just bought a new sensor and tested it - it works! I am getting .45v out of it at room pressure, and a little over 1.1v when I app...

I dug a little deeper into the wiring diagrams and found the test values that confirm my original understanding that this should give a 0-5v output signal.

Now I'm back to believing it's just a bad sensor.

I'm trying to do some custom A/C controls and I need to know how this particular sensor works. So far it is not as I expected. Here's what I know: The sensor is a three-wire pressure sensor on the receiver/drier of a 2002 Mercedes-Benz CLK55. The Denso part number is 499000-7060 and the Mercedes par...