radiator fans
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Joined: Sep 2007
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05 c55 silver, 98 Imperial Red C43
radiator fans
When exactly are these fans supposed to kick on?
I was told they are supposed to always be on but their speed changes with the temperature of the engine. Mine only come on when the AC is on and they are on full blast.They dont come on AT ALL at any other time.
What I did to try and solve this is replace the relay that sits inside the fender and make sure the fuses are fine. Next I want to replace the coolant temperature sensor but Im not sure exactly where it sits.
Can someone show me where the sensor is and shed some light on how these fans are supposed to function
I was told they are supposed to always be on but their speed changes with the temperature of the engine. Mine only come on when the AC is on and they are on full blast.They dont come on AT ALL at any other time.
What I did to try and solve this is replace the relay that sits inside the fender and make sure the fuses are fine. Next I want to replace the coolant temperature sensor but Im not sure exactly where it sits.
Can someone show me where the sensor is and shed some light on how these fans are supposed to function
MBWorld Fanatic!
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From: A.D., U.A.E
2000 (W202 C200) & 2000 (W202 C55)
Only one fan will operate when you switch-on A/C, both will working when temp. reaches (90c) or A/C gas temp. become higher than (88c), [[that of course depend to the country spec]]..!
First, you have to check the gas, cause gas sensor has directly related to the Aux. speed function,
make sure temp. sensor is working, and plug not move or loose,,
also, if "gas tank sensor" or "gas pressure sensor" not working properly, it will interrupt the signal in Aux. fans controller..!!
ZAYED,,
First, you have to check the gas, cause gas sensor has directly related to the Aux. speed function,
make sure temp. sensor is working, and plug not move or loose,,
also, if "gas tank sensor" or "gas pressure sensor" not working properly, it will interrupt the signal in Aux. fans controller..!!
ZAYED,,
MBWorld Fanatic!
Joined: Aug 2006
Posts: 7,053
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From: A.D., U.A.E
2000 (W202 C200) & 2000 (W202 C55)
Temp. sensor located left side of thermostat,,
and gas tank sensor & gas pressure sensor located behind driver side headlight(both attached to the gas tank itself)..
ZAYED,,
and gas tank sensor & gas pressure sensor located behind driver side headlight(both attached to the gas tank itself)..
ZAYED,,
MBWorld Fanatic!
Joined: Jan 2007
Posts: 1,152
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From: Sydney, Australia
190D 2.5 (x2), 190E 2.6, W202 C240,W202 C43 (C55), W210 E55, W212 E250CDI
Aux fans should be working together, not separately. They will mainly come on for the A/C. If the A/C condenser pressure exceeds 15bar then the fans will gradually ramp up to full speed as the pressure increases. I don't think they run for the engine until the engine temp exceeds 98-100C (can check if you need the exact figure).
If the fans are running excessively especially when the engine is still warming up then check both the condenser pressure and temp using the A/C control panel. If the pressure is high (18+bar) but the temperature is low (
If the fans are running excessively especially when the engine is still warming up then check both the condenser pressure and temp using the A/C control panel. If the pressure is high (18+bar) but the temperature is low (
MBWorld Fanatic!
Joined: Jan 2007
Posts: 1,152
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From: Sydney, Australia
190D 2.5 (x2), 190E 2.6, W202 C240,W202 C43 (C55), W210 E55, W212 E250CDI
There may still be market differences but this is the basic specs for the W202 Aux fans (2 in front of the radiator)
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Junior Member
Joined: Jun 2012
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From: Coeur d'Alene, Idaho
1998 C43 AMG
HI all - I'm an amateur mechanic at best. Would someone please advise how to get to the aux fan relay that is inside the fender? And also let me know exactly what the relay is called so I can order it from www.mbdirectparts.com? Thanks for your help!
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MBWorld Fanatic!
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From: Land of mountains, cheese, chocolate and watches
12' W204 C63 AMG coupe "T-Rex", 12' W451 Smart Fortwo Pulse (99' W202 C43 AMG + Ultima Can-Am sold)
HI all - I'm an amateur mechanic at best. Would someone please advise how to get to the aux fan relay that is inside the fender? And also let me know exactly what the relay is called so I can order it from www.mbdirectparts.com? Thanks for your help!
MBWorld Fanatic!
Joined: Mar 2010
Posts: 5,889
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From: Land of mountains, cheese, chocolate and watches
12' W204 C63 AMG coupe "T-Rex", 12' W451 Smart Fortwo Pulse (99' W202 C43 AMG + Ultima Can-Am sold)
Yes that's better. OP talked about behind the driver's headlight 
Thanks Zayed.
Thanks Zayed.
