AC problem - Benzworld.org

JQ · 03-03-2003, 01:44 AM

All of the sudden the EC (Economy?) mode on my AC can not be swiched off. Light goes off when de-frosting, but in auto-mode it goes to EC which I guess means compressor is not working. Any clue?

mike krzeminski · 03-04-2003, 07:57 AM

while ignition ON and engine running,
press and hold "REST" for at least 6 seconds
to enter Diag mode
then use LEFT auto button to scroll to page 7
(you have digit 7 in the left field) and check
for refrigerant pressure, when mine died (due
to punctured radiator) it was showing 02. normally
i think it is 50.

press REST again to exit diag mode

m

JQ · 03-04-2003, 08:32 AM

Thanks for the tip, I will check it tonight!

I knew about this diagnostic mode (BTW, the diagostic mode speedo is very accurate, I compared it with a GPS), but I did not know how to use it to trouble-shoot.

If it is a puctured radiator, is it a warranty issue (still have one month left)?

JQ · 03-05-2003, 07:23 AM

I checked diag menue 7 and it shows 02 bar which I guess means the coolant has no preassure.

I also checked in defrost mode (then the EC light goes off), no difference.

It would be interesting to know what the preasure is on a car with a functioning AC but the EC-mode activated (= compressor off I guess). If this would also show the same low pressure, my problem could be electronics, and that the compressor for some reason does not get a signal to go on.

Norseman · 03-05-2003, 01:49 PM

Is this diag thing somthing that works only with the climatronic, with the screen? or is it something you can do with the regular ac unit as well?

JQ · 03-06-2003, 02:29 AM

I guess its only for the automatic AC. Does your AC have a "rest" button? It if does, try pressing it, it could use maybe one of the displays in the instrument cluster.

The speedomenter is really. In my car it showed +/- 1km/h correct untlil 220 km/h with a GPS as a reference.

JQ · 03-17-2003, 08:37 AM

Got the AC fixed under warranty last week. There was a leakage. Maybe it had something to do with the car not being used, standing at the dealer between June 2001 and April 2002 when I bought it.

Peter Guenther · 03-18-2003, 05:26 AM

My ( 2001) EC button illuminated, and would not turn off. The dealer indicated that it shows no pressure in the system. They evacuated replaced a sensor and recharged, works fine. I was not aware of the diagnostic function indicated above.