Any ideas to check would be appreciated.
Do you hear a clicking noise? Sometimes dirty condenser coils or a broken condenser fan can cause this problem. If your coils are very dirty this could be the problem.
It is also possible that the thermostat is broken or you have a faulty condenser.
This site shows how to check your thermostat :http://www.partselect.com/refrigerat...tat+repair.htm
Frequently if it is a condenser problem, the fault is actually in the relay that causes the condenser to kick on, but the condenser itself is actually good.