Hello all,

I went to a shop to have my AC diagnosed because it wasn't cooling well. They recharged it; it works better now, but it's still not great, especially in idle traffic.
I noticed my auxiliary cooling fans never turn on, no matter how hot the engine gets!
After doing some troubleshooting I ended up disconnecting the AC pressure switch located on the receiver/drier.
It has 4 pins
I shorted two of the pins on the harness that leads to the switch and the fans turned on.
So I assume the switch is defective.

Now here's the big problem I'm facing: The MB dealership located the part based on my VIN; they say it has a 3-pin connector. But my pressure switch has 4 pins. I can't find a 4-pin switch anywhere. Does anyone have any idea how to locate this 4-pin switch?
Thanks!