- What if the radiator fan turns on only when the AC is on but overheats when is off?
- Why does my radiator fan only turn on with AC?
- Should cooling fan come on when AC is on?
- What are the symptoms of a faulty cooling fan switch?
- Can a bad thermostat cause radiator fan not to work?
- Does the coolant temp sensor control the fan?
- Should radiator fan run all time?
- What sensor controls the radiator fan?
- What causes cooling fans not to come on?
- At what temperature does the radiator fan turn on?
- Will AC work without cooling fan?
- How long does it take for the cooling fan to turn on?
What if the radiator fan turns on only when the AC is on but overheats when is off?
The most likely culprits are a thermostatic switch, fan resistor, temperature switch, low-speed or high-speed relay, or a wiring issue. ... When the vehicle has the AC on, the engine needs extra help cooling so the ECU commands the fan to be on any time the AC is on.
Why does my radiator fan only turn on with AC?
Most likely the temperature sensor that operates the fan under normal circumstances is faulty. The AC controls may operate the fan from a place in the control circuit after the normal temp sensor so everything is OK when the AC is on. Also the Fan may be on continuously when the AC is operating.
Should cooling fan come on when AC is on?
Both radiator fans should always run when the AC compressor is engaged. Both radiator fans should always run when the coolant temperature sensor in the bottom tank of the radiator reaches about 212*F.
What are the symptoms of a faulty cooling fan switch?
Bad Cooling Fan Relay Symptoms
- The engine runs hot or overheats. Is the engine running hotter than usual? ...
- The cooling fans don't work. ...
- The cooling fans keep running. ...
- Warning lights. ...
- Poor air conditioning performance. ...
- Normally open relay. ...
- Normally closed relay. ...
- Dual relay.
Can a bad thermostat cause radiator fan not to work?
If the thermostat is stuck open (allowing coolant to flow) it can cause the engine to run cooler than normal so obviously the fan wouldn't come on.....but not like the engine/coolant can be running too hot and the thermostat somehow effects the sensor reading or operation of the fan.
Does the coolant temp sensor control the fan?
The sensor works by measuring the temperature that's being given off by the thermostat and/or the coolant itself. The temperature is then sent to the on-board control system. ... As the control system receives the temperature from the CTS, it may trigger the cooling fan to either shut off or turn on.
Should radiator fan run all time?
An electric fan SHOULD NOT run all the time. ... The fan turning on is normal and a consequence of the hot coolant, not a cause. The coolant may not be moving due to a water pump problem, blockage in the radiator or hoses, or a stuck valve, i.e., the “thermostat” in the coolant line.
What sensor controls the radiator fan?
In both cases, the control units use a temperature sensor to know when to start the radiator fan. If this temperature sensor is broken, the control unit will not know when to start the radiator fan. Some cars use separate engine coolant temperature sensors for the radiator fan and the engine control unit.
What causes cooling fans not to come on?
Six things may prevent an electric cooling fan from coming on: Defective temperature switch, coolant sensor or other sensor. Engine thermostat is stuck OPEN (engine never gets hot enough to turn on the fan) Faulty fan relay.
At what temperature does the radiator fan turn on?
Your radiator fan should kick in at about 200 degrees Fahrenheit. If you notice your vehicle is overheating or at the very least running hotter than it normally does, listen for the fan to see if you can hear it.
Will AC work without cooling fan?
If air isn't flowing over it, it won't exchange the heat it needs get rid of so the A/C core inside the vehicle can become cold and make you comfortable. If the fan didn't come on, you'd still be warm inside. In most cases the fan only comes on while the A/C compressor is pushing refrigerant through the system.
How long does it take for the cooling fan to turn on?
Turn the air conditioning to the maximum setting – this should spark the cooling fan to immediately come on. In older cars, this typically takes about 15-20 minutes for the engine to reach the right temperature. If there's a problem with the engine's temperature, then this can damage the radiator.