Auto Air Conditioning & Heater Repair: Air Conditioning, electronic leak detector, jeep grand cherokee

Question
  I have a 1996 Jeep Grand Cherokee(Canadian).   I have refilled the AC system with 134a refridgerant but it hasn't worked.   The problem is that the compressor only runs for about 2 or 3 seconds every minute or so while the AC is on.   What could be causing this?  

I have checked the fuse and it is fine.

There is a relay in the engine compartment and when the compressor does kick on I can feel a movement inside the relay.  

Answer
You need to put a set of A/C gages on the system and engage the compressor in order to determine if you have enough freon in the system. If the freon is low according to the pressures that you read on the gages, It is most likely due to a leak, You have to install a can or two of freon and check the system with an electronic leak detector to determine where the leak is. Fix the leak and recharge the system with the proper amount of freon for your type of system as amounts vary from system to system and vehicle to vehicle.