W140 S600 1996
AC pipe ruptured a year ago and needed replacing.
System lost all gas of course, at which point the EC indicator light (for Economy mode,switches off AC compressor, probably sensible if there is no gas in the system anyway) came on and stayed on. When it was repaired and the system re-gassed, the mechanic showed me the 'new way' of getting the AC to come on.
(to be continued)

 

When you first turn the ignition, the EC light comes on, press EC button to turn it off. It doesn't turn off the first time, so turn off the ignition, then turn it on again, press EC button a second time, EC indicator light goes out. Start engine, all fine. There is no other obvious way, I have tried many other combinations.
(to be continued)

 

Since the AC mechanic knew how to do this, it must be a known problem, although he did not offer a solution.

Anyone else had this issue? Or more importantly, does anyone know how to fix it, as it is a bit of a nuisance?
Regards

 

If you want to turn on the AC while already driving, you either have to stop the car and do as above, or put the transmission into neutral, press EC button, switch off engine.

 

Then switch on ignition again,

 

while coasting without PAS or PAB, press EC mode button again to get the light off, re-start engine,

 

put back into gear, drive on. Inconvenient, dangerous and probably illegal.

 

Almost as difficult as getting this site to accept a post

 

It seems this website has fixed some issues as the posting issues have improved. Interesting A/C EC info, will remember it if needed.
thanks.

 

that is not normal, does your mechanic have a scanner to erase fault? otherwise you will need to take it to a mechanic who has the proper tool, what modle is your MB and series? to get you the full service manual.