Operation CHARM: Car repair manuals for everyone.

Low Refrigerant Detection

The controller monitors the state of the low pressure cycling switch, if the compressor has been activated, and measures the duration of the compressor "On" time.

The minimum compressor "On" time limit will be 1.5 seconds. Once this limit (less than 1.5 seconds) has been exceeded for 10 consecutive cycles the compressor will be turned off and remain off until the servicing has been performed and the battery disconnected to reset the memory.

The A/C indicator shall flash for a period of 2 minutes and then turn "Off" when the low charge condition has been detected. It shall also flash at every ignition cycle for 2 minutes until the servicing has been performed and the battery disconnected to reset the memory.