Mr-V

Hi All,

Happy new year, thanks for all the great effort you put in to make these forums so rich with content.

My 2010 C Class Sport (W204) ended 2017 with no heating (on the way to the airport to collect mum :eek) and I was hoping someone could give me some guidance on where to start and how to diagnose the issue. The climate control will turn on and follow all of the settings available to it, but it will not heat the air. I have checked the blower motor from the engine bay and it is clear and spinning, I am able to feel cold air being blown out. I have read that a heater resistor located under the dash in the cabin could be the cause, can anyone help me understand the role of these and other parts in delivering heat? MB dealer wants £120 just to take a look. :


Thanks in advance for your assistance and support

MrV
#firsttimeposter

JimmyKudo

Hey Mr-V, I had the same issue; I'm not sure if it's the heater control valve in the engine (which I believe redirects hot coolant over the heater core) or the resistor below the dash. I heard the resistor only works for a few minutes to give electrical heat while the engine is warming up. Can you confirm what the issue was if you did end up going to the dealership? If I find out, of course I'll do so as well.

Best,
JimmyK

Mr-V

Thanks for your reply JimmyK. I wasn't able to get the problem solved. Hoever, after approx 4 days the heating started to work.

I did wait for approx 55mins into my journey (mostly motorway) before turning it on. it's started blowing hot air almost immediately.

Could this be an indication that it's more in relation to the heater control valve?

I have since had the same issue 1 other time. I turned the car on in the morning. Did 10miles, only got cold air. Stopped for fuel and restarted, I got hot air.

Thanks again !