Climate Control R230/2003
 

Since some time I have a curious problem with the automatic climate control unit. With selector on "automatic" even after a short drive the system starts to heat excesively and the vent-fans turn at full power. The heat is then well above the selected temperature on the climate control unit. Only after about 20min driving time the system re-regulates itself to normal levels without any manipulation from the driver.
Anybody had the same occurence/problems? Is it eventually the temp-sensor?
Suggestions? Solutions? Thank you in advance for your help and advises.

Frank

It seems that I have found the problem. The car was driven very seldom
during the winter season. The 2nd battery in the trunk got de-charged.
(Warning indication on the display). It seems that the climate control
automatic system does it's own "reset" and thereafter re-adjust itself.
As I'm driving now more regular with the car and I do not have this problem
any longer. Therefore it is recommended to have the 2nd trunk battery on a
permanent charger-unit when parked for more then one week.

Frank

Your car should be able to take a week off with out the rear battery going dead. Sounds like a new battery is in order.

I put the battery tenders on when I know the car is going to sit for a month or more just to be safe.

My 05 had the rear battery go bad after 2 years in service and was replaced under warranty.

Absolutely. If it goes dead or nearly so after only a week, change it. A large battery like that should be able to hold a decent charge for a month or more even with the draining "convenience" features of the SL. I think that because of their frequent charge/discharge cycles though, the convenience batteries don't last as long as others -- quite possibly only a few years or so.

Rook