Engine fan ON at all time.
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Viper 1994, ZR-1 1991 and RX-7 1993
Engine fan ON at all time.
Hello,
Cold weather here, northern Quebec. Average -12°C (10°F).
Engine fan turns on (and stays on). Coolant temperature shows a steady 91°C (196°F).
Heater blows not so warm air.
No CEL, however when I read the codes there is something (sorry didn't note which code it is). When I erase the code, fan turns off instantly, and sometimes the problem is solved for the rest of the day. Next morning, fan is still off until engine reaches some temperature. Have to erase the code again...
I don't even think I need that fan right now to be honest. I tried to pull fuse #22, without success. Is there a way I can temporarily disable the fan until I figure out what's the issue?
Thanks!
Cold weather here, northern Quebec. Average -12°C (10°F).
Engine fan turns on (and stays on). Coolant temperature shows a steady 91°C (196°F).
Heater blows not so warm air.
No CEL, however when I read the codes there is something (sorry didn't note which code it is). When I erase the code, fan turns off instantly, and sometimes the problem is solved for the rest of the day. Next morning, fan is still off until engine reaches some temperature. Have to erase the code again...
I don't even think I need that fan right now to be honest. I tried to pull fuse #22, without success. Is there a way I can temporarily disable the fan until I figure out what's the issue?
Thanks!
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12 C63BS Magno Alanite Grey, 25 X5 Msport, 08 BMW E93, Ducati Hyper 698
So you have a code and fan is not working right, you clear code and fan works right.
So guessing code will tell you what is wrong, maybe make note of it and don’t clear it.
car can still overheat if idling at any temp so would not recommend disabling fan, but easy way is unplug fan harness at the fan.
So guessing code will tell you what is wrong, maybe make note of it and don’t clear it.
car can still overheat if idling at any temp so would not recommend disabling fan, but easy way is unplug fan harness at the fan.
Thread Starter
Junior Member
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Viper 1994, ZR-1 1991 and RX-7 1993
So you have a code and fan is not working right, you clear code and fan works right.
So guessing code will tell you what is wrong, maybe make note of it and don’t clear it.
car can still overheat if idling at any temp so would not recommend disabling fan, but easy way is unplug fan harness at the fan.
So guessing code will tell you what is wrong, maybe make note of it and don’t clear it.
car can still overheat if idling at any temp so would not recommend disabling fan, but easy way is unplug fan harness at the fan.
Before I had that problem, I never heard that fan running (I only drive the car in winter time). It is very cold and windy here. I'm sad to read that the car could still overheat.
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Viper 1994, ZR-1 1991 and RX-7 1993
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MBWorld Fanatic!
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From: Kitchener, ON
2010 C63 AMG
Sounds like the thermostat has failed (stuck open). It throws a code when you first start the car which turns the fan on high. Clearing the code returns the fan to normal operation.
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Thread Starter
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Viper 1994, ZR-1 1991 and RX-7 1993
Again this morning: OBD2 scanner shows 0 code, however when I erase everything the fan stopped. Been running for 60 kms afterwards, everything runs as it should.
Before I erased the code, temperature was at a (solid) 91°C. As soon as I erased it (5 seconds later), it dropped to 70°C...
Thanks for your help guys.
Before I erased the code, temperature was at a (solid) 91°C. As soon as I erased it (5 seconds later), it dropped to 70°C...
Thanks for your help guys.
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From: Alexandria, VA
07 E63 AMG, 10 C63 AMG, 07 E63 Designo, 07 E350, 09 C300, 07 C230
It's a Thermostat, is given your ECU conflicting signals. I had the same type of issue but with my Oil Temperature Sensor, thereby causing my oil cooler fan to run.
We replaced the sensor, reset to parameters in the ECU using Star Diagnostics, and problem solved.
We replaced the sensor, reset to parameters in the ECU using Star Diagnostics, and problem solved.
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Viper 1994, ZR-1 1991 and RX-7 1993
So are you suggesting that it could be the coolant temperature sensor?
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From: NY
2010 C63 2019 GLA45
It may not be the thermostat.
Get a Xentry scan of the car.
I like to mess around in Xentry and try all the tests and things.
I tried a reset once and it turned the fan on permanently. It may have been the inidovual test /reset for the cam adjusters, not the teach in process.
Then I did a general reset and this was solved.
Get a Xentry scan of the car.
I like to mess around in Xentry and try all the tests and things.
I tried a reset once and it turned the fan on permanently. It may have been the inidovual test /reset for the cam adjusters, not the teach in process.
Then I did a general reset and this was solved.
Thread Starter
Junior Member
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Viper 1994, ZR-1 1991 and RX-7 1993
It may not be the thermostat.
Get a Xentry scan of the car.
I like to mess around in Xentry and try all the tests and things.
I tried a reset once and it turned the fan on permanently. It may have been the inidovual test /reset for the cam adjusters, not the teach in process.
Then I did a general reset and this was solved.
Get a Xentry scan of the car.
I like to mess around in Xentry and try all the tests and things.
I tried a reset once and it turned the fan on permanently. It may have been the inidovual test /reset for the cam adjusters, not the teach in process.
Then I did a general reset and this was solved.
I broke a nipple on the thermostat so I've got to order a new one anyway.
But I still couldn't figure where that coolant temperature sensor is.
Very limited information about these cars here. Maybe I should post a DIY.
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Viper 1994, ZR-1 1991 and RX-7 1993
Thread Starter
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Viper 1994, ZR-1 1991 and RX-7 1993
I am confused now.
Thread Starter
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Viper 1994, ZR-1 1991 and RX-7 1993
Thanks a lot for your pictures Mort, maybe the dealership reversed both sensors...
Anyway, I did not change the sensor, but I changed the thermostat this afternoon. So far so good... I will post if the problem comes back!
Thanks everyone!
Anyway, I did not change the sensor, but I changed the thermostat this afternoon. So far so good... I will post if the problem comes back!
Thanks everyone!
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Since you changed the thermostat, has the problem occurred again? My car has the same issue now.
Thread Starter
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Viper 1994, ZR-1 1991 and RX-7 1993
