[Z06] at what temp does the cooling fan come on?
11-20-2011, 04:45 PM
#1
Burning Brakes
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at what temp does the cooling fan come on?
burned out the fan relay wiring harness on the z(fan runs all the time)
even at 55-65 deg w/ no vararam cruising around, the car heats up pretty quick to 220ish deg. car is fine on the highway running in the mid 170's. is this car suppose to shoot up to those temps that quick? i get off the highway after running 176deg cooling temps after about a mile of cruising and sitting at a stop light for a few minutes the car is over 210 deg. is it suppose to heat up +35deg that quick? things should go back to normal after replacing the relay as i never see over 180 in these temps w/ the vararam.
even at 55-65 deg w/ no vararam cruising around, the car heats up pretty quick to 220ish deg. car is fine on the highway running in the mid 170's. is this car suppose to shoot up to those temps that quick? i get off the highway after running 176deg cooling temps after about a mile of cruising and sitting at a stop light for a few minutes the car is over 210 deg. is it suppose to heat up +35deg that quick? things should go back to normal after replacing the relay as i never see over 180 in these temps w/ the vararam.
11-20-2011, 05:32 PM
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Not unusual to see temp go up like that if fan isn't on. Here is the description of the cooling fan operation:
The engine cooling fan is a variable speed fan. The engine control module (ECM) controls the fan speed by sending a pulse width modulated signal to the cooling fan control module. The cooling fan control module varies the voltage drop across the cooling fan motor in relation to the pulse width modulated signal.
Cooling fan speed is effected by many different conditions and can be adjusted from 10 percent to 90 percent duty cycle (PWM), 90 percent is considered high speed fan. When multiple cooling fan speed requests are received the ECM uses the highest cooling fan speed of all the requests. The ECM commands the cooling fan ON under the following conditions:
• Cooling fan duty cycle starts when engine coolant temperature reaches approximately 95°C (204°F) and reaches high speed at temperatures above 113°C (235°F).
• Cooling fan duty cycle starts when A/C pressure reaches approximately 1100 kPa (160 psi) and reaches high speed at A/C pressures above 2480 kPa (360 psi).
• At engine oil temperatures above approximately 150°C (302°F) the cooling fan duty cycle will be commanded to high speed.
• At transmission oil temperatures above approximately 132°C (270°F) the cooling fan duty cycle will be commanded to high speed.
• After the vehicle is shut OFF if the engine coolant temperature at key-off is greater than 113°C (235°F) or the A/C pressure is greater than 1720 kPa (249 psi) the cooling fan duty cycle is set to 50 percent, low speed. If the coolant temperature drops below 110°C (230°F) and the A/C pressure drops below 1660 kPa (241 psi) the fan will shut OFF. The fans will automatically shut OFF after 2 min. regardless of coolant temperature.
Programming the fan to a 100% duty cycle will definitely shorten component life since the components have more heat build up due to more energy in the circuit and no chance to cool off as they would at a lesser duty cycle.
Bill
The engine cooling fan is a variable speed fan. The engine control module (ECM) controls the fan speed by sending a pulse width modulated signal to the cooling fan control module. The cooling fan control module varies the voltage drop across the cooling fan motor in relation to the pulse width modulated signal.
Cooling fan speed is effected by many different conditions and can be adjusted from 10 percent to 90 percent duty cycle (PWM), 90 percent is considered high speed fan. When multiple cooling fan speed requests are received the ECM uses the highest cooling fan speed of all the requests. The ECM commands the cooling fan ON under the following conditions:
• Cooling fan duty cycle starts when engine coolant temperature reaches approximately 95°C (204°F) and reaches high speed at temperatures above 113°C (235°F).
• Cooling fan duty cycle starts when A/C pressure reaches approximately 1100 kPa (160 psi) and reaches high speed at A/C pressures above 2480 kPa (360 psi).
• At engine oil temperatures above approximately 150°C (302°F) the cooling fan duty cycle will be commanded to high speed.
• At transmission oil temperatures above approximately 132°C (270°F) the cooling fan duty cycle will be commanded to high speed.
• After the vehicle is shut OFF if the engine coolant temperature at key-off is greater than 113°C (235°F) or the A/C pressure is greater than 1720 kPa (249 psi) the cooling fan duty cycle is set to 50 percent, low speed. If the coolant temperature drops below 110°C (230°F) and the A/C pressure drops below 1660 kPa (241 psi) the fan will shut OFF. The fans will automatically shut OFF after 2 min. regardless of coolant temperature.
Programming the fan to a 100% duty cycle will definitely shorten component life since the components have more heat build up due to more energy in the circuit and no chance to cool off as they would at a lesser duty cycle.
Bill
Last edited by Bill Dearborn; 11-20-2011 at 05:37 PM.
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11-20-2011, 07:30 PM
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Burning Brakes
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Not unusual to see temp go up like that if fan isn't on. Here is the description of the cooling fan operation:
The engine cooling fan is a variable speed fan. The engine control module (ECM) controls the fan speed by sending a pulse width modulated signal to the cooling fan control module. The cooling fan control module varies the voltage drop across the cooling fan motor in relation to the pulse width modulated signal.
Cooling fan speed is effected by many different conditions and can be adjusted from 10 percent to 90 percent duty cycle (PWM), 90 percent is considered high speed fan. When multiple cooling fan speed requests are received the ECM uses the highest cooling fan speed of all the requests. The ECM commands the cooling fan ON under the following conditions:
• Cooling fan duty cycle starts when engine coolant temperature reaches approximately 95°C (204°F) and reaches high speed at temperatures above 113°C (235°F).
• Cooling fan duty cycle starts when A/C pressure reaches approximately 1100 kPa (160 psi) and reaches high speed at A/C pressures above 2480 kPa (360 psi).
• At engine oil temperatures above approximately 150°C (302°F) the cooling fan duty cycle will be commanded to high speed.
• At transmission oil temperatures above approximately 132°C (270°F) the cooling fan duty cycle will be commanded to high speed.
• After the vehicle is shut OFF if the engine coolant temperature at key-off is greater than 113°C (235°F) or the A/C pressure is greater than 1720 kPa (249 psi) the cooling fan duty cycle is set to 50 percent, low speed. If the coolant temperature drops below 110°C (230°F) and the A/C pressure drops below 1660 kPa (241 psi) the fan will shut OFF. The fans will automatically shut OFF after 2 min. regardless of coolant temperature.
Programming the fan to a 100% duty cycle will definitely shorten component life since the components have more heat build up due to more energy in the circuit and no chance to cool off as they would at a lesser duty cycle.
Bill
The engine cooling fan is a variable speed fan. The engine control module (ECM) controls the fan speed by sending a pulse width modulated signal to the cooling fan control module. The cooling fan control module varies the voltage drop across the cooling fan motor in relation to the pulse width modulated signal.
Cooling fan speed is effected by many different conditions and can be adjusted from 10 percent to 90 percent duty cycle (PWM), 90 percent is considered high speed fan. When multiple cooling fan speed requests are received the ECM uses the highest cooling fan speed of all the requests. The ECM commands the cooling fan ON under the following conditions:
• Cooling fan duty cycle starts when engine coolant temperature reaches approximately 95°C (204°F) and reaches high speed at temperatures above 113°C (235°F).
• Cooling fan duty cycle starts when A/C pressure reaches approximately 1100 kPa (160 psi) and reaches high speed at A/C pressures above 2480 kPa (360 psi).
• At engine oil temperatures above approximately 150°C (302°F) the cooling fan duty cycle will be commanded to high speed.
• At transmission oil temperatures above approximately 132°C (270°F) the cooling fan duty cycle will be commanded to high speed.
• After the vehicle is shut OFF if the engine coolant temperature at key-off is greater than 113°C (235°F) or the A/C pressure is greater than 1720 kPa (249 psi) the cooling fan duty cycle is set to 50 percent, low speed. If the coolant temperature drops below 110°C (230°F) and the A/C pressure drops below 1660 kPa (241 psi) the fan will shut OFF. The fans will automatically shut OFF after 2 min. regardless of coolant temperature.
Programming the fan to a 100% duty cycle will definitely shorten component life since the components have more heat build up due to more energy in the circuit and no chance to cool off as they would at a lesser duty cycle.
Bill
