R129 2001 SL500 A/C Problem--Please help a newbie
 

I have a 2001 SL500---only has 19000 miles and the A/C is acting up---dealer said no code fault---A/c will not engage when button pushed, but if I leave the button pushed and the meters showing on high (4-5 bars) the A/C will come on eventually and run a few seconds and then go off again and continue to come on and off randomly but in short burst ---- it is very cold when it comes on, so it is charged, the heat does the same thing

please help if anyone can suggest a fix

The fix is to get the dealer to do their job. The AC could be cutting off for a number of reasons that would not throw a code, like a bad temp or pressure sensor.

Have they put a set of gauges on the system, or watched what's going on with the real-time data monitoring of the diagnostic system?

Someone else is having this problem. See this thread: http://www.benzworld.org/forums/r129-sl-class/1397241-99-ac-compressor-wont-engage-fans.html.