I didn't know where to post this, I've got an 89 Bronco II but it's got an Explorer 4.0 with a 4.0 AC system. I installed a brand new AC kit, minus the two switches and evaporator. Installed them this past Sunday. I put the vacuum pump on and pulled a nice vacuum for about two hours. Disconnect the vacuum pump, hook up the freon can. Start the truck and turn on the AC. Compressor does not turn on. I spent the next three hours trying to figure it out. WOT relay is good. All fuses are good. Low refrigerant is not an issue at this point as the compressor clutch does not engage to pull the freon into the system. The control unit is getting power. I repaired what wire breaks were in the wiring harness, taped them and loomed them. I'm probably going to have to pull the dash and check the wiring. Not looking forward to that especially in this heat which is why I wanted AC to begin with.