Cooling fan won't shut off?
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MBWorld Fanatic!
Joined: Jun 2007
Posts: 2,208
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From: Westmont, IL
2014 C63 Sedan
Cooling fan won't shut off?
hello everyone, so my radiator cooling fan would kick in whenever I would start the car in the morning, and it would shut off after a couple minutes or so, but yesterday and today it just keeps going while the car is running, anybody have ever had this issue? or know what it could be? bad relay? sensor?
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Joined: May 2010
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2008 W204
hello everyone, so my radiator cooling fan would kick in whenever I would start the car in the morning, and it would shut off after a couple minutes or so, but yesterday and today it just keeps going while the car is running, anybody have ever had this issue? or know what it could be? bad relay? sensor?
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MBWorld Fanatic!
Joined: Jun 2007
Posts: 2,208
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From: Westmont, IL
2014 C63 Sedan
I remember me and my father changed the water pump on his old S430 and we put everything back together started the car and the fan stayed on permanently like your situation. Turns out we forgot to reconnect the connection for the sensor that reads the temperature. See if your temperature gauge is getting a proper reading of ~85 Celsius when fully warmed up, if not this could indicate a bad sensor. I remember we got no reading at all on the gauge when it was unplugged. It's possible your car is getting no temp reading so it blasts the fan on full to be safe, however I'm no mechanic.
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MBWorld Fanatic!
Joined: Sep 2007
Posts: 1,481
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From: Southeast
2008 C300 Sport, RWD, US
What did you do to correct i?.
I think I may be having the same problem.
It was only around 75 degrees today.
When driving at 70ish, I don't hear the fan. As I slow down to 30ish, the fan seems to come on very loud. Don't know if it just need lubrication or what. When I come to a stop, its also fairly loud. After turning off, it stays on for a few seconds and then turns off.
Is there any lubrication recommendations for this radiator fan?
This is on a 2008 C300 early production with around 82,000 miles on it.
I think I may be having the same problem.
It was only around 75 degrees today.
When driving at 70ish, I don't hear the fan. As I slow down to 30ish, the fan seems to come on very loud. Don't know if it just need lubrication or what. When I come to a stop, its also fairly loud. After turning off, it stays on for a few seconds and then turns off.
Is there any lubrication recommendations for this radiator fan?
This is on a 2008 C300 early production with around 82,000 miles on it.
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Joined: Feb 2004
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From: SEATTLE WASHINGTON USA
'08 C300 Lux Barolo Red Beige Leather P2 MM 18" wheels '84 944
What did you do to correct i?.
I think I may be having the same problem.
It was only around 75 degrees today.
When driving at 70ish, I don't hear the fan. As I slow down to 30ish, the fan seems to come on very loud. Don't know if it just need lubrication or what. When I come to a stop, its also fairly loud. After turning off, it stays on for a few seconds and then turns off.
Is there any lubrication recommendations for this radiator fan?
This is on a 2008 C300 early production with around 82,000 miles on it.
I think I may be having the same problem.
It was only around 75 degrees today.
When driving at 70ish, I don't hear the fan. As I slow down to 30ish, the fan seems to come on very loud. Don't know if it just need lubrication or what. When I come to a stop, its also fairly loud. After turning off, it stays on for a few seconds and then turns off.
Is there any lubrication recommendations for this radiator fan?
This is on a 2008 C300 early production with around 82,000 miles on it.
MBWorld Fanatic!
Joined: Sep 2007
Posts: 1,481
Likes: 2
From: Southeast
2008 C300 Sport, RWD, US
It's a lot louder which may just mean that it's running faster for not much reason. I would understand it if it was on some of our 100 degree days but it's just not been all that hot. Even on our 100 degree days, I don't recall it being so loud that it would draw attention to itself. On the other hand, it's been so quiet up to the last week that I though it had stopped working completely. A few weeks ago, I did add some MB antifreeze. Wonder if that did something to the system or maybe I inavertantly bumped a wire?
While we're at it, where is the sensor that the radiator fan uses to tell it(or possibly the controller/electronics) how fast to run?
While we're at it, where is the sensor that the radiator fan uses to tell it(or possibly the controller/electronics) how fast to run?
Last edited by JimPap; Mar 26, 2012 at 07:08 AM.
Thread Starter
MBWorld Fanatic!
Joined: Jun 2007
Posts: 2,208
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From: Westmont, IL
2014 C63 Sedan
I was away on vacation and have not been on here. But this problem is still not fixed on my car. We'll take it in for sure sometime this week. But I did talk to my mechanic about it and he said he had a w203 C230 with the similar issue before. Let me know if any luck with yours
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
30 A 004 153 97 28 TEMPERATURE SENSOR
ON FRONT SIDE,REAR 001
Frequently this problem is the fan controller which is on a captive lead with the fan assembly. You require to replace the entire fan assembly.
ON FRONT SIDE,REAR 001
Frequently this problem is the fan controller which is on a captive lead with the fan assembly. You require to replace the entire fan assembly.
Thread Starter
MBWorld Fanatic!
Joined: Jun 2007
Posts: 2,208
Likes: 22
From: Westmont, IL
2014 C63 Sedan
Thread Starter
MBWorld Fanatic!
Joined: Jun 2007
Posts: 2,208
Likes: 22
From: Westmont, IL
2014 C63 Sedan
What did you do to correct i?.
I think I may be having the same problem.
It was only around 75 degrees today.
When driving at 70ish, I don't hear the fan. As I slow down to 30ish, the fan seems to come on very loud. Don't know if it just need lubrication or what. When I come to a stop, its also fairly loud. After turning off, it stays on for a few seconds and then turns off.
Is there any lubrication recommendations for this radiator fan?
This is on a 2008 C300 early production with around 82,000 miles on it.
I think I may be having the same problem.
It was only around 75 degrees today.
When driving at 70ish, I don't hear the fan. As I slow down to 30ish, the fan seems to come on very loud. Don't know if it just need lubrication or what. When I come to a stop, its also fairly loud. After turning off, it stays on for a few seconds and then turns off.
Is there any lubrication recommendations for this radiator fan?
This is on a 2008 C300 early production with around 82,000 miles on it.
MBWorld Fanatic!
Joined: Sep 2007
Posts: 1,481
Likes: 2
From: Southeast
2008 C300 Sport, RWD, US
tasho3
Any idea which wiring connection? Hate to take it in if all I need to do is to clean a connection.
Glyn
Wasn't able to find the sensor using the diagram. Was that for the 2008 C300 sport?
Any idea which wiring connection? Hate to take it in if all I need to do is to clean a connection.
Glyn
Wasn't able to find the sensor using the diagram. Was that for the 2008 C300 sport?
Super Moderator
Joined: Jun 2008
Posts: 19,942
Likes: 192
From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
Thats where it is for all 272/273. See white blanker here at 5 o' clock in relation to the vacuum pump blanker plate with screws around it above the cps. Ignore cps arrow in red.
MBWorld Fanatic!
Joined: Sep 2007
Posts: 1,481
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From: Southeast
2008 C300 Sport, RWD, US
Glyn,
I didn't have any luck getting to the sensor and I'm assuming that I'm in the right place. That place being between the firewall and the engine block. I couldn't get my hand down there to see if there was a loose wire.
Approaching this from a different direction, where is the radiator fan controller?
I didn't have any luck getting to the sensor and I'm assuming that I'm in the right place. That place being between the firewall and the engine block. I couldn't get my hand down there to see if there was a loose wire.
Approaching this from a different direction, where is the radiator fan controller?
MBWorld Fanatic!
Joined: Sep 2007
Posts: 1,481
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From: Southeast
2008 C300 Sport, RWD, US
Finally made some more progress.
It's looking like there is a malfunction in my air conditioning compressor which occurs after its been running for about 30 minutes where the head pressure gets high and sends a signal to the fan to turn on high to try to cool it down. I don't really loose cold air until it gets to a certain temperature.
Turns out the fan is doing exactly what its suppose to be doing.
Have to return car on Tuesday as it was late in the day before they figured it out.
An interesting aside, the electronics indicated that the a/c system was o.k. but the tech (shall we call him yoda) put gages on the a/c and found the problem. Guess some of these electronics aren't doing what they're suppose to be doing.
We'll see next week if their diagnosis is correct.
It's looking like there is a malfunction in my air conditioning compressor which occurs after its been running for about 30 minutes where the head pressure gets high and sends a signal to the fan to turn on high to try to cool it down. I don't really loose cold air until it gets to a certain temperature.
Turns out the fan is doing exactly what its suppose to be doing.
Have to return car on Tuesday as it was late in the day before they figured it out.
An interesting aside, the electronics indicated that the a/c system was o.k. but the tech (shall we call him yoda) put gages on the a/c and found the problem. Guess some of these electronics aren't doing what they're suppose to be doing.
We'll see next week if their diagnosis is correct.
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Joined: May 2015
Posts: 132
Likes: 1
2000 C230 Kompressor
Exactly which bad wiring? The wire going into fan controller? Wire between fan controller and fan motor? Could you provide more clarity. Thanks
