mopar 8/23/2010if low on rifrigerant...low pressure switch kicks...if too full high pressure switch kicks...clutch won't kick in...safety device....more than likely it probably needs a little charge. auto parts stores have charge systems with built in guages...so you don't have to second guess...
darkmind 8/23/2010Also check the condition of your magnetic clutch relay.
HouseCallAuto 8/23/2010AC high pressure switch on the back of the compressor is the number one cause of the AC clutch not engaging. It is assumed that the system is fully charged and not just low on refrigerant.