Auxillary Cooling Fan Runs Constantly
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Auxillary Cooling Fan Runs Constantly
My 1998 E320 auxillary cooling fan runs all of the time - even at start up. I believe that it is supposed to kick on after a certain temperature is reached
(100 degrees). Can I just replace the thermostat or could it be a sensor that needs replacing and how would I go about checking? New thermostats are relatively cheap - $20 or so and I would imagine relatively easy to install. Thanks to anyone that can help.
(100 degrees). Can I just replace the thermostat or could it be a sensor that needs replacing and how would I go about checking? New thermostats are relatively cheap - $20 or so and I would imagine relatively easy to install. Thanks to anyone that can help.
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From: Kansas City. U.S.A.
2000 E320 Sedan
it will be somewhat a challege to diagnose. I say start as follows:
1) Check Radiator and Antifreez level, Radiator could be goign bad, or antifreez could be low. See if not fixed then,
2) Check engine oil level if low or not.
3) Replace thermostat. If not fixed then:
4) Possible senstors. If not
5) Take it to the shop
1) Check Radiator and Antifreez level, Radiator could be goign bad, or antifreez could be low. See if not fixed then,
2) Check engine oil level if low or not.
3) Replace thermostat. If not fixed then:
4) Possible senstors. If not
5) Take it to the shop
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Thanks E320Star,
My oil and coolant levels are fine, the engine runs great and does not get hot at all. I'm quite sure that the problem is either the thermostat or a sensor telling the fan to kick on even though it is not supposed to yet.
My oil and coolant levels are fine, the engine runs great and does not get hot at all. I'm quite sure that the problem is either the thermostat or a sensor telling the fan to kick on even though it is not supposed to yet.
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Joined: Aug 2002
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From: Kansas City
97 E420 90 300E
Im assuming that you dont have the air conditioning on right. Because I know they automatically run full time when the ac is on. My mechanic had a hell of a time putting my thermostat in. Took about 45 min. Good luck
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From: Kansas City. U.S.A.
2000 E320 Sedan
when mechincal repairs been you done on the car the past 60k miles like:
1- Have u ever replaced thermostat?
2- Flushed radiator?
3- Replaced Water pump?
....etc jst to get a history of the car?
Thanks
1- Have u ever replaced thermostat?
2- Flushed radiator?
3- Replaced Water pump?
....etc jst to get a history of the car?
Thanks
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Joined: Nov 2001
Posts: 3,860
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From: Jacksonville Florida
209/W210 Estate /W211 modded by MBENZNL
Unplug the Cooling Fan sending unit aka 212 switch @the Engine and see if the fans stop..if so the switch is defective....seen several do this
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Joined: Jun 2005
Posts: 138
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From: Huntsville Alabama
'00 E430, '83 Porsche 928S
I am not sure on the benz, but it may have a relay in the fuse panel for the aux fan. Sounds like a relay stuck. I think the fan on the w210 is triggered by the same temp sensor that gives the computer information. I would think you would see other problems if that sensor was bad.
