Why does my fan come on as soon as I start my car?
If the fan comes on, you may have a bad temperature sensor or gauge. 2. A cooling fan temperature switch (or sensor, in some vehicles) can also get stuck, which may cause the fan to run continuously any time you turn the ignition key on or start the engine. Troubleshoot the switch.
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.
Why does my cooling fan keep coming on?
Cooling fans stay on at all times
If the cooling fans are staying on at all times, this is another (less common) symptom of a possible problem with the cooling fan relay. If the relay shorts internally, it may cause power to be permanently switched on, which will cause the fans to run at all times.
What are the symptoms of a faulty cooling fan switch?
Symptoms of a Bad or Failing Thermo Coolant Fan Switch
- Engine overheating. Engines generate an enormous amount of heat and as a result are subjected to very large temperature swings if this switch does not operate effectively.
- Check Engine Light comes on.
- Broken or shorter signal wire.
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.
Should radiator fan turn on when AC is on?
Both radiator fans should always run when the AC compressor is engaged. To check the temperature at which the fan comes on, turn the A/C off and keep the engine running until it reaches normal operating temperature. Most fans should come on when the coolant reaches about 200 to 230 degrees.
When should the radiator fan kick 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.
Why does my radiator fan turn on and off?
To avoid a further rise of temperature, the fan induces air flow. 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?
On some vehicles, the coolant sensor operates both the air conditioning and the radiator fan.
Why does my radiator fan not turn off?
If the fan doesn’t stop running, plug that sensor back in and unplug the coolant temp sensor on the thermostat housing. If the fan stops running, replace that sensor. If the fan still runs after unplugging both sensors, then problem might be with radiator fan control module located behind the glove box.
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.
What causes the radiator fan to stop working?
A fan failure, or a failure of the fan relay or control circuit is bad news because it can allow the engine to overheat. Engine thermostat is stuck OPEN (engine never gets hot enough to turn on the fan) Faulty fan relay. A wiring problem (blown fuse, loose or corroded connector, shorts, opens, etc.)
How do you diagnose a bad cooling fan?
Symptoms of a Bad or Failing Cooling/Radiator Fan Motor
- Cooling fans do not come on. The most common symptom of a faulty cooling fan motor are cooling fans that do not come on.
- Vehicle overheating. Another symptom of a possible problem with the cooling or radiator fan motors is the vehicle overheating.
- Blown fuse.
How can I tell if my radiator fan is bad?
If your radiator fan has a fan clutch, check the radiator fan while the motor is running. The radiator fan should be running at more RPMs than the motor. If it is not, the fan clutch is bad and needs to be replaced. Some radiator fans are solid mounted, with no fan clutch.
How do you test a radiator fan?
Unplug the fan connector closest to the fan. Make up some jumper cables. Then connect them directly, from the battery to the fan motor, to see if it spins. Consequently, if it does not spin it is blown.