A/C Compressor Will Not Come On

Reader Question My question is:

– A/C compressor not engaging

– 2005 Town & Country.

– The A/C light comes on in the van. I am not able to hear the A/C Compressor engaging when the button is turned on.

– The 15 amp fuse & relay are good in the fuse box under the hood. I checked the relay by using another one in the fuse box.

– This is the first time trying to use it this year. Last year it worked fine.

Thanks for your help,
Mike

Hello Mike,

The first thing I would do is check the A/C system Freon level and pressure with A/C gauges. If you have a small Freon leak in the system and enough Freon has leaked out the low pressure A/C switch will not allow the compressor to come on.

Sometimes with the new R134A Freon systems just a small amount of Freon added to the system will be enough to allow the compressor to come on. You should then have the system checked for a Freon leak, since it is NOT normal to have to periodically add Freon to the system.

If the Freon level checks out OK and you still have problems I would then test the electric cooling fan motor that is up in front of the radiator. This electric fan is needed for the A/C system and the fan should be ON when the A/C compressor is ON. This fan is controlled by a relay and gets a signal from the A/C control head inside the vehicle and the on board computer.

Unfortunately both suggestions are not very easy to test yourself at home and really should be done by a trained mechanic, unless you know what you are doing. Adding too much Freon to the system can do damage.

Blessings,

Austin Davis