Does your 'climate control' panel have a small screen like this one below? If so, you can run a diagnostic to narrow down the problem.

Are you sure that your refrigerant is not low? This version of the a/c unit has a couple more external sensors than the other one, so I'm not sure that they are interchangeable.... It needs checking out from the circuit diagram.

 

hello mate, yes it does have that one now, but the red and blue buttons are solid rather than the little triangles if that makes sense

how odd to join a fourm and you are from norfolk as well lol....im in thorpe st andrew

 

havent checked the refridgerent to be honest, it stills blow hot even when the rest button is lit and i mean hot....i did wonder if there was a duo valve or anything like that??

robinsons also said they think there are a coupel of stepper motors gone for the flaps not moving

but start with the panel.....i just cant see that a panel older wouldnt work

all in all i love the car, but its so hot lol

 

I believe what Keyhole was alluding to is the climate control damper reset, and this works on most all modern MBZ climate control systems. With the engine running, press and old the "RECIRC" and "FRONT DEFOG" buttons simultaneously until their indicator lights begin to blink. Release the buttons and watch the blinking lights. The airflow should cycle through a few changes, and the light will stop blinking after about 20-30 seconds. This resets the climate control panel and test the damper servos. If the indicator lights never stop blinking, then it means there is a problem with damper control system, which is most likely due to either bad servos or broken linkages.

 

I believe what Keyhole was alluding to is the climate control damper reset, and this works on most all modern MBZ climate control systems.

Well - I wasn't referring to that one (I call it 'normalizing') but it is a good idea...

What I was talking about is the a/c diagnostic test for checking the a/c sensors. I am not the author - I found it some while back. Here is how I have saved (and abridged it) in my files. It works fine on my W209 a/c system shown above.

Introduction

The Mercedes E-class air conditioning is a complicated system of blower motors, computers, relays, switches, and refrigeration parts. With a system this complex, it’s likely that you’ll encounter an air conditioning problem at some point during your ownership. Thankfully, the onboard climate control computer has a self-check mode that can help you quickly diagnose air conditioning problems.

Collect Sensor Data

First we’ll get the values of all the various climate control sensors. These sensors constantly monitor data like air temperature, refrigerant pressure, etc. Odds are if something’s wrong, a sensor will pick it up. Let’s get started!

Start your car. Press the “AUTO” button on your climate control.
Turn on the A/C (i.e. “EC” light must be off; if the light won’t shut off, continue with this test.

Let the car idle for about 3 minutes.
Set the temperature on each side to 72°F. You can do this quickly by pressing both the red and blue arrows simultaneously.

Press and hold the “REST” button for five seconds or until the left side of the display says “01.” The left side indicates which sensor you’re checking. In this case, #1 is the in-car temperature sensor. The right side of the display shows the value of sensor #1 (in this case, the actual in-car temperature).

Press the “AUTO” button on the left side to move to the next sensor. Press the “AUTO” button on the right side to move to the previous sensor.

Record the ID number of each sensor (left side of display) and its corresponding value (right side of display). For example, in the picture on the right, you would record that sensor #5 has a value of 6.
You only need to do this for sensors #1-8. You can write down the values for the other sensors, but they’re not really related to air conditioning function.

When you are done, press the “REST” button again to exit the self-check mode.

A/C Sensor Values. Enter the values from each sensor.

Sensor 1 - Inside Temperature:*
Sensor 2 - Outside Temperature:*
Sensor 3 - Left Heater Core Temperature:*
Sensor 4 - Right Heater Core Temperature:*
Sensor 5 - Evaporator Temperature:*
Sensor 6 - Engine Coolant Temperature:*
Sensor 7 - Refrigerant Pressure:*
Sensor 8 - Refrigerant Temperature:*

doug - The W209 does not have duovalves. W208 does.

 

hello mate, yes i tried that they dont stop blinking.....at the moment im trying to get it to not blow full out hot

which vents are next

thanks for your help and advice though im willing to try anything :bowdown:

 

@Keyhole - Interesting - I know all of that is available via SDS, but I did not know it was accessible locally through the A/C controls.

@Doug - It sounds like you have a problem in the damper system. Now you need to get someone with SDS to check the codes (a generic OBDII scanner won't do it - only MBZ SDS). This will tell you which specific part(s) are not working. Unfortunately, damper system repairs aren't easy - they require a lot of dash parts disassembly to get to the culprits.

 

yeah i know mate, at the moment im just trying to get it to stop blowing extereme hot all the time

I just cant beleive that the aircon panels all dont fit and work, MB reckon I have a older panel in my car than the car is and want me to spend £690 on a new panel from them.....which for the age of my car is just silly

Ill worry about the dampers next when I can sit in it and not roast my nuts off :crybaby2:

Besides I can always use MB for what wrong and get a Indy to do the work if I cant do it myself

 

Just wait a few months- you'll be glad that your heater is roasting your nuts off.

 

im so angry its untrue......so turns out that when i pulled the aircon panel out to check the part number thats it it, some fool (not me) hadnt plugged in the smaller plug into the back of the panel....

plugged it in, done the normalise......blowing cold as a cold thing and all the vents are moving around now....

jesus, just goes to show trust no one except yourself to do anything on your car

thanks keyhole for the tip it was kind of that which prompted me to pull the panel off

 

Hi,

do you remember the steps that you took to pull the aircon panel and check the wirings?

I have experienced a similar situation, where the vents are blowing full hot air even if the temp has been reduced to low.

I do believe the AC requires a refill, however I still wouldn't expect the heat to be so intense as times during the summer periods.

 

Use plastic trim tools to lever it out from the sides , it is held in by two metal spring clips.
Search on youtube you will find a video .

 

Yes, you do pry it from the dash:

https://benzbits.com/w209/Radio/ClimateControl.jpg

But first, there are two screws on the bottom of the ACC panel that must be removed before prying it from the dash:

https://benzbits.com/w209/Radio/ClimateControlScrews.jpg

To get to those screws, you must remove the ashtray assembly:

https://benzbits.com/w209/Radio/AshtrayTab.jpg

To get to it, you must first pull the panel that the shifter is in:

https://benzbits.com/w209/Radio/ConsolePanel.jpg

And before that, you should remove the shifter by prying its chrome trim from the console panel and then releasing the twist-lock nut so the knob can be bulled from the shaft:

https://benzbits.com/w209/Radio/KnobRetainer.jpg

 

Yes , my mistake ,,sorry I forgot about those screws,,it has been a while..
My notes,,
1. Prise up shifter boot first and then the chrome bezel. Reach under to bend the plastic tabs back a little ,they can break easily ,,and then your chrome bezel will not sit flush.
2. Remove shifter trim panel , using a hook tool to pull up at the FRONT edge on the two metal tabs so as not to break the plastic tabs.
Gear knob can stay on. Have the Trans in Neutral position.
3. Pry ash tray at edges .
4. Remove two T20 torx screws ..45 degree angle.
5.Remove ac panel by prying at each side.