QB320

Hello everyone. I have a problem with my A/C. Here's the 411.

I turn on the A/C and the compressor engages. After a few minutes, the compressor will disengage and will stop blowing cold air.

The only way I can get the compressor to engage again is to turn off the car and wait for about 30 sec to 1 min. You'll hear a "tick" sound. After that, I can turn on the car and A/C again and the same problem will occur in a few minutes.

What's strange is that even if I turn off the A/C for an hour or more, and turn it on again, the compressor will not engage unless I turn off the car as I described above.

I read in the manual that the EC light will remain ON if refrigirant is low. Mine didn't do that but I took it in to get it checked out anyway. They added some 134a and also told me the pressure was fine.

Any help would be appreciated.

Thanks in advance,
JL

MARK CUMMINS

The Shop Should Have Look Into your complaint
Sounds Like a Couple Of Things
Low Pressure switch ..causes the A/C Compressor to shut off

Evap temp sensor ...Causes the A/C Compressor to shut off

QB320

I went into the A/C diagnostics mode and here's what I found out.

The evap temp showed 150deg. I turned on my A/C. It was blowing cold air for about 3 minutes and the compressor disengaged. I checked the evap temp and it showed 156deg.

I think this is what is causing the compressor to disengage.

I guess my next question is how much will it cost to change this sensor? Can I do it myself? Could there be another problem which results in the incorrect evap temp reading other than the faulty sensor itself?

Thanks for all your help.

clkal

my car has the exact problem (1999 clk430). I also brought the car to an authorized dealer and they told me my coolant level was fine. If you end up figuring out how to fix the problem, please let me know as it is the middle of summer and I dislike driving in the heat w/o AC....LOL...thanks

MARK CUMMINS

The Sensors do Fail!
If the readings are what you posted..I Would Go to the dealer and get a Evap temp sensor .. its a 15/20min job. drivers side of the console/carpet must be removed to replace it

QB320

sounds easy enough. Maybe I'll try it this weekend. Do you know where exactly the sensor is? Also, will I need a R134a recharge after I replace the sensor??

Thanks.