w 208 Radiator Fan running at full speed
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clk320 w208
w 208 Radiator Fan running at full speed
Pulled into my garage after an uneventful, but pretty moist day (Florida). Turned off the car and walked around the back to go into my home and the FAN started running FAST. Went back and started it to see what the engine temp was, barely above 80. Turned the car off, Full Speed again. I decided to wait a few minutes, it did not slow down. I have pulled the connection off of one side of my battery till I figure this out. The car sat for 4 hours, connected the battery back up, Full Speed Fan immediately.
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From: Florida
2002 CLK 55 AMG cabriolet Eurocharged
Sounds like a short circuit,
Try removing the fan fuse and see if it is shorted to another circuit. There is a fan thread in the 208/209 AMG forum going on now. Seems the fan has a control module as well linked into the ECM. very costly fix.
I think we can control the fan without a $7K fix though.
Cheers, Gator
Try removing the fan fuse and see if it is shorted to another circuit. There is a fan thread in the 208/209 AMG forum going on now. Seems the fan has a control module as well linked into the ECM. very costly fix.
I think we can control the fan without a $7K fix though.
Cheers, Gator
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clk320 w208
Update:
I disconnected battery again after reading a couple of threads. To let it sit in the garage for a few days in case moisture had gotten into a circuit. Connected battery up after 4 days, no fan running, hmm. Started car, reset all the abs, roof, windows, radio, everything. Went around the block 5 times, popped the hood, temp was barely over 80, looked at fan, dead still. Parked it in the garage and left it there for 4 more days ( I have another car to drive). Went out to crank it up and NO Nothing, Dead, Dead Battery, beyond Dead. Couldn't get into the trunk with anything, so I hooked my charger to the post under the hood, FAN starts running, very slow of course. I Disconnected the fan with the connector near the shroud, charged a few minutes and got into the trunk. Disconnected the battery from the car and charged it for 6 - 7 hours. Started the car (fan still disconnected), reset all the stuff again and turned the car OFF. Connected the cooling fan back up,, FAN Roars to a breakneck speed. Start the car, Fan STOPS, even when temp got back up to midrange, it never spun while the car was idleing. Turned car OFF, Fan Spins up to Fast again. Geeesh, battery is still connected now, but Fan is Disconnected, going to see how the battery does. THANKS
I disconnected battery again after reading a couple of threads. To let it sit in the garage for a few days in case moisture had gotten into a circuit. Connected battery up after 4 days, no fan running, hmm. Started car, reset all the abs, roof, windows, radio, everything. Went around the block 5 times, popped the hood, temp was barely over 80, looked at fan, dead still. Parked it in the garage and left it there for 4 more days ( I have another car to drive). Went out to crank it up and NO Nothing, Dead, Dead Battery, beyond Dead. Couldn't get into the trunk with anything, so I hooked my charger to the post under the hood, FAN starts running, very slow of course. I Disconnected the fan with the connector near the shroud, charged a few minutes and got into the trunk. Disconnected the battery from the car and charged it for 6 - 7 hours. Started the car (fan still disconnected), reset all the stuff again and turned the car OFF. Connected the cooling fan back up,, FAN Roars to a breakneck speed. Start the car, Fan STOPS, even when temp got back up to midrange, it never spun while the car was idleing. Turned car OFF, Fan Spins up to Fast again. Geeesh, battery is still connected now, but Fan is Disconnected, going to see how the battery does. THANKS
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From: Florida
2002 CLK 55 AMG cabriolet Eurocharged
If there is no fan relay then a logic circuit has failed, You can isolate the circuit with an ammeter across each fuse testing for amperage draw.
The battery might have a shorted cell that can cause an abundance of problems, It is such a large CCA that it might not be noticeable until car use. Have the battery load tested at a local auto parts store first, 5 years is good for a battery in Florida.
Once the drain is isolated we can determine how to correct it. Sounds like a short.
Gator
The battery might have a shorted cell that can cause an abundance of problems, It is such a large CCA that it might not be noticeable until car use. Have the battery load tested at a local auto parts store first, 5 years is good for a battery in Florida.
Once the drain is isolated we can determine how to correct it. Sounds like a short.
Gator
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clk 200k
That a fan would start working once an engine is stopped is perfectly normal. The water keeps circulating due to temperature difference, the radiator heats up, there's no fresh air due to car movement, the fan starts. No problem here. Of course, if the fan still starts after the car rests four a few hours, there should be a problem.....
I just wanted to call for your attention that it's the radiator temperature that should command the fan, not the engine temperature that you read in the instrument panel. Maybe you'd like to measure the radiator temperature to be able to derive valid conclusions. Maybe you'd like to check the thermostat inside the radiator, which should be the single responsible sensor for fan driving.
Last edited by humbfig; Jul 30, 2013 at 04:43 AM.
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2015 GL550 4matic
Is the front fan for cooling the radiator? I thought the cooling fan was the mechanical one behind the radiator, connected to the water pump, and the front fan is for A/C?
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clk320 w208
So, You all know, I am still stepping thru this. I need to locate all of the sensors now.
When running the CAR, fan does not move. Taking a drive, dash temp barely goes above 80. Pull into my drive, pop hood, Fan dead still. Turn off car, pull key, fan roars to life and goes at a breakneck speed.
Have disconnected the fan at the shroud, as it WILL kill my battery.
When running the CAR, fan does not move. Taking a drive, dash temp barely goes above 80. Pull into my drive, pop hood, Fan dead still. Turn off car, pull key, fan roars to life and goes at a breakneck speed.
Have disconnected the fan at the shroud, as it WILL kill my battery.
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clk320 w208
Update: To set the stage, I'm a computer guy and one of my customers is a Ford dealer. That dealership has actually done all my maintenance on my Benz's for over 7 Years. The master mechanics there are very proud of their ability to fix Anything.
Here is my Trial solution to my fan problem, from them. Since it is a two conductor fan, they placed a Ford dropping resistor in my engine bay, wired it to my electrical system so that.. The fan runs pretty fast when idling, slows way down when engine speed increases as alternator creates more power. Turn car off and fan stops dead. No more relay or sensor control of the engine fan. Going to see now if any side effects occur.
Here is my Trial solution to my fan problem, from them. Since it is a two conductor fan, they placed a Ford dropping resistor in my engine bay, wired it to my electrical system so that.. The fan runs pretty fast when idling, slows way down when engine speed increases as alternator creates more power. Turn car off and fan stops dead. No more relay or sensor control of the engine fan. Going to see now if any side effects occur.
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CLK 320
I had this happen to me out of the blue like that. Started up all of a sudden when I pulled in off a rainy drive and the fan was blowing fast and a check engine light popped on. Ignored it at first, but then I became suspicious because it was getting into winter and It was always blowing. I didn't want to burn out the fan, but I hate electrical stuff so went ahead and took it to the shop. Turns out it was a short circuit that had been caused by a mouse (squirrel, some kind of rodent) that had chewed through the engine harness wiring. The shop was able to fix it by apparently just soldering the wire and insulating it again.
Best of luck!
Best of luck!
