Expert: Roland Finston - 8/11/2011

Question
QUESTION: I have 2001 Chrysler Town and Country and the A/C unit keeps cutting in and out.  I have had it in the shop for about the past 6 weeks trying to figure out what the problem is.  The A/C unit originally was not getting the signal to start the compressor.  They replaced the Front Control module and Relay box and now it works about 75% of the time.  Most of the time, it seems to start working after I have been driving it for at least 15 minutes or so.  If it is stop and go traffic, it tends to not want to start.  Once it does start cooling, it will occasionally stop.  If I turn it off and back on, it will sometimes restart it.  Other times it won't.  Do you have any idea what is causing this and any suggestion on what to try to get this fixed?  Thank you!

ANSWER: Hi Marla,
I am tied up with an errand but I will get back with an answer this afternoon.
Roland

---------- FOLLOW-UP ----------

QUESTION: OK.  Thanks!

Answer
Hi Marla,
There are several operating conditions and electrical circuits that need to be satisfied/functional for the compressor clutch to be energized.  My thought would be to get a fault code readout using a device that plugs into a socket under the dash and which accesses the memory of the engine and the body computers for stored code numbers that may tell us what is going on to cause this behavior. You can get a free code readout at many nationwide autoparts stores such as Autozone or from an independent repair shop for $40 or less. Ask for the four-digit code numbers, what they, and what repair would be suggested. Then write back to me with that inforamtion and we can compare to the manual and decide what course to follow.
Roland