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Matt
Matt, Engineer
Category: Australia Car
Satisfied Customers: 21359
Experience:  Automotive Engineer for 20 years, BEng hons degree,
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I have recently purchased a 2000 E240 Mercedes sedan with

Customer Question

I have recently purchased a 2000 E240 Mercedes sedan with approx 210,000 kms on the clock. The car runs beautifully and is quiet and very smooth Small problem has developed though. When I start the care the A/C fan blower works on all settings. After about 5 minutes the fan cuts out completely. Moving the fan speed switch doesn't effect it.
The fault will occur on any fan setting. The fan stops blowing for between 20 seconds and two minutes, then comes back on as normal.
It will only do this two or three times and only in the first 15 to 20 minutes. Once it has come back on for the third (Approx) time it will stay on for as long as I am driving. Up to two or three hours.
Unsure if it could be the fan speed resistor or the motor itself.
When it is working it works correctly on all or any speed setting. When it cuts out, changing the speed position switch doesn't effect it.
It is a manual setting type system.Any suggestionsRegards
Barry Heames
Submitted: 4 months ago.
Category: Australia Car
Expert:  Matt replied 4 months ago.

Hello

the fan assembly is in under the passenger side glove box. you remove the cover and the fan scroll assy can then be removed

There should be a plug and socket and the speed control diode. Check that you have 12 v at the input and that all connections are secure. if you have the siemens climate control , then you may have to look into the sender module on the dashboard

, if it is the standard heater unit the switching is much more robust and basic, very unlikely to give a problem.

its quite possible that the speed diode may need replacing and another common issue is motor brushes failing so check those over too

brushes can be found here

http://www.ebay.co.uk/itm/Mercedes-Heater-Blower-Motor-Carbon-Brush-Brushes-PAIR-/110603767473?rmvSB=true&hash=item19c07f8eb1&pt=UK_CarsParts_Vehicles_CarParts_SM&clk_rvr_id=1150922969056

Expert:  Matt replied 4 months ago.

Hi

do you still need help?

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