NO HEAT - Mercedes ML 270 cdi 2002 w163

The car has been stood for over 6 weeks whilst i was recovering from my operation
When I finally started it, i eventually realised that there was NO heat coming in the car !
The engine temperature was sitting at less than 10 degrees all the time, the dashboard was at... -2.0 to 3.0 degrees if i was driving it would be less than 2.0, and if i was stationery with the engine running it may go up to 3.0 degrees... (and that is still... COLD)
It was suggested by someone that my Thermostat is stuck in the open position, and is faulty and would need replacing
I have replaced the thermostat and the engine temperature is now always around 89 degrees (approximately), so this means that my previous thermostat WAS in fact faulty, and the old thermostat had a rattle coming from it too.
HOWEVER....However, although the engine temperature has now gone up to > 87 degrees...... nevertheless i am not getting any heat in the car, even though I have extensively bled the cooling system after flushing it !....
Please someone help...we are freezing !


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BMWadict made a comment.
1 year 5 months ago

You are correct that the problem is typically the thermostat stuck open which you confirmed. 

What happenes is that air may be stuck in the heater core and therefore you are not getting any hot air. 

Check the coolant level when the car is cold. 

Also remove the cap and let the car idle and also rev up the engine a few times. Does the coolant level drop? If so, add coolant. 

If the problem remains you may also want to read the codes from the A/C heater control unit and clear the codes. When the unit detects a problem it can prevent it from operating properly. 

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13enzy made a comment.
1 year 5 months ago

Is there a machine/scanner that I can use (other than a STAR scanner) which I could buy and use my self to read/clear codes for Mercedes benz ML 270 cdi Auto 2002 model ?

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MBFanatic made a comment.
1 year 4 months ago

Yes there are. 

Here is your answer:



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