Opposite of fans stay running
#1
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My fans come on at full speed w/AC as they should (very quiet in comparison to some other cars I've owned), but they do move a **** pot of air, feels like standing behind a jet engine, lol. But, when I turn the car off they go completely off. No run down as many of my cars have done.
So would this be an indication of a faulty fan control module?
So would this be an indication of a faulty fan control module?
#2
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The fans are controlled by a couple of things. First when the air conditioning is on the ECM automatically kicks the fans on controls them. When the AC is off the fans are controlled by the fan control module mounted on the right hand side of the radiator. The fan control module receives its control signal from the Engine Coolant Temperature Sensor (ECT) Below is an excerpt from the shop manual for the fans.
If they are not coming on as noted you need to check the temps with an infared thermometer and determine if the temp shown on gauge is matching the temp you read. If not it maybe the ECT.
If you determine it is the fan control module you will need to find a used one. A new one is only sold with a complete fan assembly I think.
Two variable speed electric cooling fans are housed in the cooling fan shroud for the cooling of the radiator. The speed of the electric
cooling fans are adjusted by the cooling fan motor control module, which is controlled by the engine control module (ECM).
The ECM determines the cooling fan speed by receiving inputs from the engine coolant temperature (ECT) sensor and the dual automatic
temperature control module (DATC). The ECM sends a variable pulse width modulated (PWM) signal to the fan motor control module to
operate the cooling fans at the required speed. The cooling fans are operated at slow speed when the engine coolant temperature is at
95°C (203°F) and are operated at full speed when the engine coolant temperature is at 105°C (221°F). A coolant temperature between
these temperatures will cause the cooling fans to be operated at a speed which is proportional to the engine coolant temperature.
When the engine is running with the ECT above 100°C (212°F), if the ignition switch is turned to the OFF position the cooling fans will
continue to operate for a time which is determined by the ECM.
If the PWM signal from the ECM to the cooling fan control module is between 7% and 95% the cooling fan control module will operate the
cooling fans at the required speed. If the PWM signal from the ECM to the cooling fan control module is below 3% and above 95% the
cooling fan control module will operate the cooling fans at maximum speed. If the PWM signal from the ECM to the cooling fan control
module is between 3% and 7% the cooling fans will not be operated.
If they are not coming on as noted you need to check the temps with an infared thermometer and determine if the temp shown on gauge is matching the temp you read. If not it maybe the ECT.
If you determine it is the fan control module you will need to find a used one. A new one is only sold with a complete fan assembly I think.
Two variable speed electric cooling fans are housed in the cooling fan shroud for the cooling of the radiator. The speed of the electric
cooling fans are adjusted by the cooling fan motor control module, which is controlled by the engine control module (ECM).
The ECM determines the cooling fan speed by receiving inputs from the engine coolant temperature (ECT) sensor and the dual automatic
temperature control module (DATC). The ECM sends a variable pulse width modulated (PWM) signal to the fan motor control module to
operate the cooling fans at the required speed. The cooling fans are operated at slow speed when the engine coolant temperature is at
95°C (203°F) and are operated at full speed when the engine coolant temperature is at 105°C (221°F). A coolant temperature between
these temperatures will cause the cooling fans to be operated at a speed which is proportional to the engine coolant temperature.
When the engine is running with the ECT above 100°C (212°F), if the ignition switch is turned to the OFF position the cooling fans will
continue to operate for a time which is determined by the ECM.
If the PWM signal from the ECM to the cooling fan control module is between 7% and 95% the cooling fan control module will operate the
cooling fans at the required speed. If the PWM signal from the ECM to the cooling fan control module is below 3% and above 95% the
cooling fan control module will operate the cooling fans at maximum speed. If the PWM signal from the ECM to the cooling fan control
module is between 3% and 7% the cooling fans will not be operated.
#3
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So today turned off all climate control, etc. Started car, no fans on at cold. Let it idle until temp gauge registered where it always maintains (just barely below straight up mid point). No fans on. Took a little drive, came back, fans running (not close to like with A/V on). Turned car off, fans go off. So I know fans are working fine, I guess my car just never gets hot enough that it calls for the fans to continue to run after driving.