SL320 Climate problem

[Paul.B]

I have a '99 SL320 with Climate Control. The problem is both persistant and annoying.

When you first start the car the system works as it should - you set a temp and the system brings the interior temp up to suit. After about 20-25 mins the through put of air disapears. The control panel shows the fan speed increase and indeed the fan speed does get faster as you can hear it but the air flow stops. It does not matter what you do with the desired temp setting or the fan control by going manual you get no air through put. The filters have been changed.
As I said it works as it should for 20-25 mins then the air stops! If you park up for a few mins (like refueling) it starts fine again and works OK for a similar period and then stops again. It is like a flap on the intake is suddenly closed

Bloody glad it has heated seats in the cold mornings!!!! My drive to work can take 90mins

Any ideas?


Paul.B

[r129sl]

Your evaporator temperature sensor has failed. This is a very cheap and easy fix, no more than £40 and easily done by DIY. It is the most common failure of the air con system on the R129. If you go to www.mercedesshop.com and do a search for "evaporator temperature sensor" in the "SL Forum", you will come up with a comprehensive answer.

[r129sl]

In the meantime, if you turn the air con off (i.e. put the system in EC mode), it will work normally but without air conditioning. This may cause your windows to mist up because, of course, air con not only cools the air but dries it.

Here is a link to a comprehensive post on the problem:

http://www.mercedesshop.com/shopforum/showthread.p...

[Paul.B]

Thanks for all the info mate. I did what was suggested and had a reading of 32 deg C on that sensor this morning! A new one is being fitted tomorrow. And yes, turning the a/c off did work. Run the car today in "ec" and it all worked as expected.


Thanks again


Paul.B

[r129sl]

Sounds like it is the sensor: a true reading of 32deg C is pretty much impossible in the UK!

Do let us know whether it solves your problem.