Hello everyone. I have a problem with the A/C on my 98 CLK320. 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

 

The (SHOP) should have checked the system for The Problem..Instead of Topping off the Freon
It Sounds Like The LOW pressure switch is defective...
Causing the A/C Compressor to shut off
And Or The Evap temp sensor Showing FALSE readings ...It Also Will cause the A/C Compressor to shut off...
Take It back and Have Them Fix It !

 

You absolutely right. 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.

 

On my '88 260E the evap. temp. sensor is accessed by removing the black cover under the steering wheel area, and possibly the tunnel wall carpet. It has a plug connection mounted to be heater box, and the temp. sensor just pulls right out. Perhaps your dealer/mechanic will be nice enough to tell you the specifics for your CLK.

 

Haha...that'll be the day. They are pretty stingy with their information.

Someone told me that the evap temp sensor can be accessed near the gas pedal (scratching your arm as you reach up there).

Can anyone confirm that this is the correct location on a W208? Is there an easier way to change it.

Thanks.
JL