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Mercedes C350e (W205) Air Conditioning Not Working.

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maturo99
Posts: 52
Joined: Mon Feb 02, 2026 8:35 pm

Salutations, all!

I need some guidance with my W205 Mercedes C350e.

When I first got the car, the air conditioner was fine, but then it just stopped working. Nothing slowed it down; it just stopped blowing cold air.

Where things stand right now:

There is refrigerant in the system.
Everything is fine with the cabin blower.
The car gets hot enough and the PTC heater is functional.
Not starting the electric air conditioner compressor.
No chilly air will be expelled from the vehicle.
We had a Mercedes-Benz dealer look over the vehicle. After reviewing the system, they confirmed that everything seems to be in order. No glaring mistake could be located.

The dealer reached out to Mercedes' technical support, and they implemented two software updates that the manufacturer had suggested; however, the issue is still present.

Mercedes claims everything is working properly, but the compressor still won't start, adding to the confusion.

Does anyone have any experience with a C350e that is comparable to this? In such case, what was the final culprit—a problem with the compressor, a sensor, a communication breakdown, the control module, the high-voltage system, or some other factor?

Would be very grateful for any advice you could give. Much obliged.
LiamTheGreat
Posts: 116
Joined: Mon Feb 02, 2026 8:35 pm

Is the gas pressure still high?If I had to guess, I'd say that was their initial move. The compressor is protected, so it won't work below a specific pressure. A tiny hole appeared in mine. After the pressure had fallen below a certain threshold, it suddenly ceased. It should display a fault code or two if it is completely non-functional.
maturo99
Posts: 52
Joined: Mon Feb 02, 2026 8:35 pm

It is true that a Mercedes dealer has checked the system pressure and refrigerant level. There was no discovery of a leak or low pressure condition, and the system is filled with refrigerant. The compressor still won't turn on, even after two software updates and the involvement of Mercedes' technical support.
IMINGAR55
Posts: 76
Joined: Mon Feb 02, 2026 8:47 pm

Does electricity reach the compressor?
LiamTheGreat
Posts: 116
Joined: Mon Feb 02, 2026 8:35 pm

Even though the controller would still display the correct pressure, a malfunctioning low pressure switch would prevent the compressor from turning on in the event that it detects low pressure. On my Audi Coupe, I had this. Uncertainty, really. Without wishing to belabour the point, it is apparent that the main dealer has overlooked something.
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