The W204 eco mode switch is non-functional.

[CheresX]

The vehicle in question is a 2011 diesel model with the code name W204.
Two weeks ago, the eco mode in my device malfunctioned, so I replaced both batteries. After the replacement, the device functioned properly and without any issues.
Unexpectedly, there is no response whatsoever when I activate the environmental button. The button fails to illuminate and the dashboard displays no information.
Do you have any insights as to the cause of this occurrence?

Thank you.

[guyskin]

There are an excessive number of conditions, and the operational state of that entity is very destructive.

[Darrellll]

To identify the issue, you should consult STAR (or iCarsoft) to determine the nature of the complaint.
 Your air conditioning system is not functioning, and the ECO Stop/Start feature is also not operational.

[Howard_silver]

Are you experiencing an auxiliary battery error?

[CheresX]

Thank you - I had never considered it before. I will replenish the system and thereafter evaluate the outcome.
Excellent guidance!

[CheresX]

Today, I had to replace a wheel sensor, so I connected Carsoft to verify the specific wheel that needed to be changed. I had no issues save for the wheel signal, so I decided to test the air conditioning system, which functioned well, as did the ECO mode. It is rather perplexing!
Regardless, I shall proceed with refilling the system.

[Blu_Ray_UK2007]

Utilise the Carsoft diagnostic tool to get the air conditioning system's pressure reading.

[CheresX]

Simple inquiry, but what is the method?

[CheresX]

Apologies, the query is not foolish; rather, it is my own lack of understanding that is at blame. I have discovered the method to do it, and when the engine is running and the air conditioning is on, the pressure increases to 13 bar. Is this favourable or unfavourable? It suggests that it is functional, but if that is the case, why did it fail to operate before (admittedly, I should have taken pressure measurements during the previous failure, but..)

[Blu_Ray_UK2007]

That is satisfactory.

[CheresX]

Under what circumstances, other than being in excellent condition, would the A/C button flash and then cease to do so? I am not detecting any problem codes from Carsoft, by the way. Thank you.

[CheresX]

I often see the suggestion that the air conditioning system must be reset after the addition of refrigerant. By what means? Is there an alternative to Carsoft?

[Paqngo]

If the battery has a low charge, for example, due to not being driven for a long or being unplugged, it may need a significant drive before the button indicating its status would illuminate. Typically, an engine restart is necessary, followed by more charging, in order for the eco indicator to turn green.