This circuit controls a vacuum pump with respect to a negative-going vacuum sensor. It turns off the pump at around 1.8V feedback from the sensor and turns it back on at around 2V. This hysteresis prevents rapid cycling of the pump.

As always the product is provided as a kit. All SMD components are soldered, you will only need to solder the cage clamps.

The vacuum sensor it has been designed for has the VAG part number 036906051G and the matching connector has number 1J0973704.

A popular pump has part number 8E0927317 with matching connector 1J0973722.

You can see a demo video here: https://youtu.be/vrhS7kEemzY

A 3D-printed enclosure has been designed here: https://openinverter.org/forum/viewtopic.php?p=29228#p29228