Digital Climate Control Units Fahrenheit vs. Celsius

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Feb 25, 2019 | 02:07 PM
  #1  
Hi folks. I'm looking to swap out the standard HVAC controls on my 2005 W203 with the digital units found on some W203s and w209s. I understand that not all models will work and at times it's a crapshoot.

There are several parts numbers listed:
- A2038304485
- A2038304385
- A2038301985
- A2038301185
And all have a variation of AC On, AC Rest, AC Off/Rest, AC buttons with different behaviors depending on model year.

I found one that is from a Canadian w209 with celsius in the display, but I have a US car. Does anybody know if the temperature displayed on these HVACs matches up with the vehicle settings or are they "hardwired" in? In other words, if my car is set up for Fahrenheit, will these automatically display in Fahrenheit? Or will they be forever in celsius because it's a Canadian or international market car? Thanks.
Reply 0
Feb 25, 2019 | 09:14 PM
  #2  
Definitely trying to make sure the right part number will work with my car. I've gone so far as matching build dates with part numbers, but I haven't called the dealer yet. Thanks for the advice.
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Feb 25, 2019 | 11:13 PM
  #3  



A203 830 44 85 worked fine on my 2005 C230. It looks much better than the analog control, but it doesn’t add all the functionality that you would receive in the cars that were equipped with the thermatronic units at the factory. I wonder whether there is a way to change from Celsius to Fahrenheit by holding down a combination of buttons.
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Mar 1, 2019 | 08:43 AM
  #4  
Use the steering wheel buttons...
Make the change from Celsius to Fahrenheit with the steering wheel controls in the Settings menu...
Also...Here is a little info on PART NUMBER and it's correlation to CHASSIS BUILD DATE...


Reply 1
Mar 1, 2019 | 08:45 AM
  #5  
Build Date is IMPORTANT;

Digital Climate Control
HVAC
Thermotronic
Option 581

(Add the SUN SENSOR and MULTI-FUNCTION SENSOR.)


Reply 1
Mar 1, 2019 | 02:30 PM
  #6  
Thank you so much, BF_JC230. You've been so helpful!

I received my climate control unit yesterday and wasted no time, installing it immediately. Mine is part no. A 203 830 43 85, coming from a 2007 W209.
As you posted, Fahrenheit and Celsius settings are informed by vehicle settings through steering wheel control buttons.

I believe most of the expected functions work-- fan control, directional control. auto (less-informed auto, since I don't have all the necessary sensors), temperature control. I am unclear as to whether the compressor control works. At least it seems like it has a mind of its own right now. So maybe my climate control unit works but doesn't fully work? When people say particular part numbers don't work with particular W203 builds, do they mean that no functions work at all?

My car was built in 5/04. As noted in the document posted above, builds up to 5/31/04 have AC button behavior where LED is off when compressor is on, while LED is on when compressor is off, because it is after all an [AC Off] button. I may need to source a A 203 830 19 85 unit.


It seems to run my AC properly for most functions. A/C REST button might not conform to my car's original AC button behavior based on build date.

On a brighter note, it seems like my car may be keyed in for REST, so that was a pleasant surprise.
Reply 0
Mar 1, 2019 | 07:50 PM
  #7  
I was able to change the settings using BF’s instructions. My car has a 9/04 build date. I have the same functionality as my analog controls. The thermatronic looks better, is easier to read and may be more accurate.
Reply 0
May 9, 2020 | 10:19 AM
  #8  
Maybe you can help with my issue I have a 2013 CLS63 AMG and was able to change to MPH and Farenheit on the front controls but the back seat digital temp control unit is still in Celcius.
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