Yes, pin 85 is the ground that is controlled by the PCM. It will ground the relay when it sees the correct signals from the high and low pressure switches.
The high side is a normally closed switch.
The low side is a normally open switch and is closed with 20 lbs of Freon in the system.
Check the pressures in the system as well as the switches themselves before assuming the PCM is the failure.
Monday, August 6th, 2018 AT 4:26 AM