ocbloke

anyone know how about problems with the climate control on a 2003 CLK320?
it has a mind of its own and switches on and off by itself and pretty much now just does nothing.
I read somewhere about performing a reset by pressing the front defrost button and air recirc button together - await the flashing lights and hey presto it is reset......that did nothing, nor did I see any flashing lights.
any guidance gratefully received.

Glyn M Ruck

Your problem can be caused by low refrigerant pressure or a faulty pressure temp switch on the condenser below the radiator.

First thing is to get an HVAC shop to check refrigerant charge. If low the system will shut down to protect the compressor. You can't diagnose anything without correct refrigerant pressure. You might have a faulty controller.

Reset procedure is in a thread called Climatronic Easter Egg on the W203 forum.

Rudeney

Glyn is right, but I would think the other functions of the climate control system would work if you turn of the A/C (press the ECON button and make sure its indicator light is illuminated). If it still acts crazy with the compressor off, and you still can't perform the test/reset procedure, then I would think it may be a bad control panel.

ocbloke

thanks for the feedback.
the AC works and the problem exhibits itself with or without the EC button engaged. the temp and functions all work but no air from the blower- it remains silent then for no reason, the blower will power up at the settings as indicated on the LCD.

Glyn M Ruck

OK ~ you have given us some more info. Check & clean fuses 30 & 41 in the front SAM. It could be the blower motor regulator. I have the P/N somewhere if needed or the blower motor itself.

I would still have the refrigerant pressure checked. While it is probably only meant to shut down the A/C circuit we have experiened low pressure affect the controller to the degree that the rear screen heater would not even switched on. I have never checked out the circuitry to understand why. I have no circuit diagram for the controller itself.

It could be the controller itself.
Good luck!

ocbloke

Thanks for the advice-
excuse my stupidity but where would one find a front SAM or the blower regulator in a 2003 CLK320?

Thanks in advance.

Rudeney

The front SAM is basically the fuse block under the hood.

ocbloke

thanks- all fuses are spotless and 'buzzed out'.
I have a dealership just up the road from me, is that the best place to get the refrigerant level checked or does someone like autozone perform that?
incidentally, there was no fuse in position 30.

Rudeney

The dealership will be the "most expensive" place for this. A good German car independent garage will be better. I don't think Auto Zone will touch an A/C system due to strict EPA regulations.

As for fuse 30 (in the cabin dash side panel), that is listed for "heat" or "A/C" recirculation, which I think is for REST, but I checked my CLK550 (which does not have REST) and it has a 40 amp fuse there. It also mentions that i's part of the TeleAid circuits, so I think I'd put a 40 amp fuse there.

Glyn M Ruck

Good catch Rudeney. I forgot these fuse numbers were in the dash side panel.

sbenzo

1996 sclass climate control unit issues. Replaced entire blower assembly also the climate control unit itself and still unpredictable blower operation and radiator fans come on immediately. Only error code is 1422 which is communication error, does anyone know if I need to sync new unit with the onboard computers? This is Drivin me crazy any HELP would be greatly appreciated. Thanks boys!

sbenzo

1996 sclass climate control unit has been replaced along with entire blower system itself and still unpredictable blower operation and radiator fans come on immediately after starting vehicle. Not sure if new unit needs to be sync with onboard computers or what. This has been a nightmare any HELP boys would be greatly appreciated!!

ocbloke

Following up on my original post, I pulled down the blower motor and removed it. bushes all good. cleaned the connections and found that when I pushed the three way connector that sits on the 'resistor' at an angle, the blower switched on. the connections are tight and snug so i am assuming that a possible open circuit exists within the potted compound of the resistor......unless anyone else can suggest otherwise.

My local MB dealer quoted me $336 just for the resistor!
the part numbers off the item are:

Behr 96192
2028207310
9140101347 803c

anyone know of a better source?

donations gratefully received

sweet jones

Great thread. My A/C has been acting up like this for a while. I'll check it all out again soon, thanks!

phingoc

292$ for the regulator here.

http://www.mbpartsworld.com/p/__/BLO...108700210.html

egwu

NEVER believe the dealer !

Enjoy :

http://www.everythingbenz.com/z/part...ower-regulator

Rudeney

If it's the blower motor regulator, it's $172 + S&H here:

http://www.parts.com/parts/2003/MERC...nent=Regulator

But that's not the part number they quoted you. 2028207310 is the blower motor switch for a W202 (late 1990's) C-Class. It's $210 at parts.com:

http://www.parts.com/parts/index.cfm...earch&siteid=2

Also note that they list MSRP of that at $292. Charging you $226 for that is just another example of dealer gouging.

egwu

Good catch Rudeney !!!

That's why you are the Guru . An updated list below:
http://www.everythingbenz.com/z/part...regulator-rear

ocbloke

Thanks everyone for their input.
I purchased a replacement resistor from Parts Geek for less than $70 delivered.
Arrived today, took less than 10 mins to change and hey presto, climate control back to life and all is well again with the world.
Unlucky this time for Foothill Ranch MBenz! Although they did take $262 at Christmas for a new key (wife lost the old one :-()
Thanks again fellow members for your guidance.

pskdude

Can anyone provide an idea where the regulator is located ? Im having the same exact issues on my end. Air just turns on and off. While in the OFF position lol...

Also Did it end up being the Blower Resistor or Regulator ?? I see 2 types on partsgeek ?

pskdude

anyone ? Anything, I know its an old thread. Should i start a new one :/

ocbloke

Hi- sorry for the delay in responding. I actually just got rid of the benz (sniff sniff) and shifted to another German (Austrian!) vehicle manufacturer!
For the location of the resistor thingy......

Passenger side, stick your head in the foot-well and look up, there (if I recall) should be some quick release screw type fasteners or proper screws- unscrew these to lower the cover. to the right is a box thing- it houses the filter, fan and pesky regulator (resistor).
the resistor looks like an aluminium heat-sink and is attached with a couple of screws and two (I think) wires.
It is in all honesty, a very simple direct remove and refit operation. Make sure you have enough light whilst down there!
above is based on my failing memory from when I replaced my regulator/resistor thingy. once replaced, all worked great once more with the climate control.

Hope that helps somewhat.

pskdude

im going crazy with this issue. I replaced the Resistor brand new and i still have the A/C shut off on me. at this point my next step is to change the a/c climate control unit. I dont believe it would be the blow motor doing this. Any thoughts ?