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Marty, Bosch Certified Master Technician
Category: Car
Satisfied Customers: 53015
Experience:  Bosch Certified Master Technician with over 35 years experience in the automotive industry.
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Sometimes my Mercedes doesnt start but a fan comes on then

Customer Question

Sometimes my Mercedes doesn't start but a fan comes on then after 5 minutes it starts. Is this normal in cold weather. 2008 C class coupe
Submitted: 2 years ago.
Category: Car
Expert:  Marty replied 2 years ago.
Hi, my name is Marty. The cooling fan turning on high when the car won't start is a symptom of a faulty engine control module or a faulty front signal acquisition module. You will need to have the car connected to the Mercedes Star Diagnosis tester to check for fault codes in both modules. The cold weather can have an adverse effect on the electronics and can aggravate the problem. Most likely there is an interruption in one of the modules that is causing this problem. A faulty electronic ignition switch can also cause a problem like this in cold weather.

Please let me know if you have any questions.


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