Leaks can occur from any part of the system. The compressor may be kicking on but it could be leaking. It's a major source for leaks as are the lines. The condenser is exposed to rocks and debris that could puncture it. So we'll charge it up and then we'll put a leak detection on it. This is an electronic leak detector. It will sense if there's any freon leaks. It will go through and make a noise sort of like that and that will tell you where your leak is as you run it along through your lines through the whole system. You also have to go inside the vehicle in the vents to make sure that the evaporator coral is not leaking because a leak can occur anywhere, down and around the compressor, on the lines. Another common problem is right at the service ports themselves which means you would have to disconnect and check for a leak right there.