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C230 W203 2006 Cooling Fan Stuck On High?

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Old Oct 2, 2019 | 02:18 PM
  #1  
Tyler Corbiere's Avatar
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Mercedes C230 W203 2006 (Sedan)
C230 W203 2006 Cooling Fan Stuck On High?

Hey guys, this is my first time posting. I have a 2006 Mercedes c230 w203 sedan.
My problem is my cooling fan (big fan covering the radiator) is stuck on high speed constantly. Even when I turn the ignition just before start, it activates and is instantly accelerated into high speed. It stays this way the whole duration of my use with the car till about 1 minute after I shut off the car and I’ve removed the key from the ignition.
My car doesn’t overheat and my coolant levels are properly filled. Ive searched for this problem on these forums but I couldn’t find my specific problem. I hope someone out there has found a solution to this problem and could help me out! This has been ongoing for about 4 or 5 months now. Took it to a shop and they couldn’t give me an answer and charged me a substantial amount in diagnosing the problem which was unfortunate.
I get a “Coolant, Visit Workshop” message on my dash screen.
I can provide any information further that could help get to the bottom of this!

Last edited by Tyler Corbiere; Oct 2, 2019 at 02:21 PM.
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Old Oct 3, 2019 | 02:43 PM
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Russell Ormerod's Avatar
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From: Cape town
not a merc
You need to check with star what faults you have in the engine ecu and also the pwm signal to the fan controller. For a w203 the fan and controller are one unit and they pretty expensive so diagnose properly first. But they do fail some times from water ingress
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Old Oct 14, 2019 | 09:22 PM
  #3  
Tyler Corbiere's Avatar
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Mercedes C230 W203 2006 (Sedan)
Originally Posted by Russell Ormerod
You need to check with star what faults you have in the engine ecu and also the pwm signal to the fan controller. For a w203 the fan and controller are one unit and they pretty expensive so diagnose properly first. But they do fail some times from water ingress
Thank you for replying I really appreciate it. By what you said first (“check with star what faults you have in the engine ecu”), did you mean just check the engine with a code reader for all codes ? And also how would I check the pwm signal? I assume I would need some type of Device for that right?
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Old Oct 16, 2019 | 05:34 PM
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leonrsa's Avatar
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From: South Africa
2004 C270CDI
There are many threads on this issue...look again!
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