Why is my radiator fan not coming on?
When your radiator fans are not coming on, it can also be caused by faulty radiator fans. The radiator fans have electrical motors inside of them, which will wear out after some years. You can test the electrical radiator fans by taking a wire from the car battery, unplug the radiator fan connector, and put 12v+ and ground into the connector.
What is the point of the radiator fan switch?
The Radiator fan was and is stupid. It has to be told when to turn on instead of being run by a direct fan. So they added a Radiator fan switch to tell the radiator fan when to turn on. Now your radiator fan is told to run, it doesn't care if your radiator cards are there or not.
Why does a VW fan need a ground wire?
VW originally used a single speed fan, that was simply controlled by a switch in the radiator. They applied 12V+ from the battery to one side of the switch, and the other went up to the fan. Since current needs a path from ground to a source. VW added a ground wire to the fan, why because the fan is mounted to a shroud,
How long does your radiator fan run after turning off?
Recently I noticed that after the car's been off for about 10-20 minutes, the radiator fan will start up and never stops on its own. I've seen it run for 25 minutes until getting worried the battery would drain. This is not after a long drive, and it's hot out, but no hotter than 85.
How do I know if my radiator fan relay is bad?
Bad Cooling Fan Relay SymptomsThe engine runs hot or overheats. ... The cooling fans don't work. ... The cooling fans keep running. ... Warning lights. ... Poor air conditioning performance. ... Swapping Relays. ... Measuring the Relay Coil's Resistance. ... Listening for Noises.More items...•
What are the symptoms of a faulty cooling fan switch?
Common signs include engine overheating, the Check Engine Light coming on, and a broken or shorter signal wire.
What causes a radiator fan to stay 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 sensor turns on the radiator fan?
coolant temperature sensorOn most modern cars, the cooling fan is controlled by the Engine Control Unit (ECU) which gets a signal from the coolant temperature sensor.
How do you test a radiator fan on a VW?
0:193:17VW A1 A2, A3, A4: Radiator fan(s) quick check. - YouTubeYouTubeStart of suggested clipEnd of suggested clipTake a metal paper clip. And you touch your power to one of the other plans. Let me shoot at lowMoreTake a metal paper clip. And you touch your power to one of the other plans. Let me shoot at low speed.
Does the thermostat control the radiator fan?
The thermostat opens and closes when there is a need to. How it works is simple. When the temperatures outside are cold the thermostat stays closed and the coolant stays in the engine. When the coolant reaches the working temperature the thermostat opens and the coolant circulates through the cooling system.
How do you test a radiator fan switch?
Testing: Before checking the radiator fan switch it is important that the ignition is switched off and the engine bay has had time to cool down. Once cool, disconnect the switch from the radiator fan, and connect the car battery to the fan motor. If the fan operates this suggests that the fan is not the problem.
Where is the cooling fan sensor located?
Its exact location also depends on its overall design. However, the coolant temperature sensor is often located right on the cylinder head or engine block. You will find it installed conveniently on a plastic hose on the coolant's inlet.
How do you bypass a radiator fan?
1:445:08How To Bypass Radiator Fan Switch - YouTubeYouTubeStart of suggested clipEnd of suggested clipThis switch i just have a jumper wire something i purchased off amazon years ago as always i'll haveMoreThis switch i just have a jumper wire something i purchased off amazon years ago as always i'll have links in the description. Box below the other thing you'll need is either a paper clip cut in half.
Why does my radiator fan stay on when my car is off?
It's normal for some vehicles to have a fan run for a few minutes after the car is shut off, generally to keep the engine cool. However, if the fan is running for an extended period, the fan itself can become damaged due to overuse.
How do you test a radiator fan resistor?
2:573:35WHAT RADIATOR FAN RESISTOR IS. WHAT IT DOES AND ... - YouTubeYouTubeStart of suggested clipEnd of suggested clipWe'll. Show you guys where we purchase ours from ours. Okay it is goes all the way like that and weMoreWe'll. Show you guys where we purchase ours from ours. Okay it is goes all the way like that and we just slide it up. So that's where it stays.
How do I manually turn on my radiator fan?
0:155:42Installing a Manual Fan Switch for Electric Radiator Fans - YouTubeYouTubeStart of suggested clipEnd of suggested clipNow any car that has an electric radiator fan can be set up with a switch now the idea is to use theMoreNow any car that has an electric radiator fan can be set up with a switch now the idea is to use the switch to ground out one of the pins on the fan control relay.
How do you test a cooling fan switch?
3:085:08Coolant Fan Switch Testing WITHOUT Removing From The VehicleYouTubeStart of suggested clipEnd of suggested clipAnd then with the jumper wire attaching one to black or one to your first paper clip. And then justMoreAnd then with the jumper wire attaching one to black or one to your first paper clip. And then just touch the other one or the red lead in this case and the fans.
What does a radiator cooling fan switch do?
When the coolant reaches a specified temperature, this switch turns on the vehicle's coolant fan, which draws air through the radiator to regulate engine temperature.
What does the fan switch do?
A ceiling fan direction switch or control adjusts the spin direction of a ceiling fan – clockwise or counterclockwise. Nearly all modern ceiling fans can be adjusted to rotate in the direction of your choice.
How does a cooling fan switch work?
0:313:04How a Cooling Fan Switch/ ThermoSwitch Works - YouTubeYouTubeStart of suggested clipEnd of suggested clipPosition which means the switch is off when the cooling fan switch reaches its optimum temperatureMorePosition which means the switch is off when the cooling fan switch reaches its optimum temperature the biometallic disc pops in the opposite. Direction.
Why is my radiator fan not coming on?
Because the radiator fan is often drawing so much power, there is often a relay that is powering the coolant fan. Of course, this relay can get damaged, which will cause the radiator fan to not coming on.
Why won't my radiator fan start?
You probably already know the purpose of the radiator and the cooling system in your car. When you are driving fast , the wind is passing through the radiator to cool the coolant down without issues , but when you are driving slow , there is no wind pushed through the radiator.
How to test radiator fan?
You can test the electrical radiator fans by taking a wire from the car battery, unplug the radiator fan connector, and put 12v+ and ground into the connector. This is the fastest and easiest way to test your radiator fans.
How to check if radiator fan sensor is working?
You need to check your repair manual of which temperature sensor controls the radiator fan and then resistance-measure the sensor with a multimeter to ensure it is functional.
Why do we use radiator fans?
When you are driving fast, the wind passes through the radiator to cool the coolant down without issues, but when you are driving slow, no wind is pushed through the radiator. This is why we use a radiator fan.
Why does my radiator fan control module fail?
This control module is often installed in the engine bay, exposed to heat and dust. This can make the control module fail after a while because of corrosion.
What is the fuse size of a fan?
The fan itself often uses a big fuse of around 50A, while there might also be a separate small fuse to the fan control module. Remember that if the fan fuse is blown – there might be a problem with the wirings or the radiator fan.
What causes a fan to go to full speed?
The large fan which is the fan module either took a dump and it's defaulting to max rpm, or one of your coolant sensors/wiring is faulting causing it to default to full speed. Check engine faults and it will tell you if the fan is bad or something else.
Why is my fan defaulting to full speed?
it's defaulting to max rpm, or one of your coolant sensors/wiring is faulting causing it to default to full speed. Check engine faults and it will tell you if the fan is bad or something else.
What Happens If The Fan in My Car Doesn’T Work? Can I Still Drive My Car?
- You can still drive your automobile without using the radiator fan, but you should never do so. When it comes to engine performance and longevity, your vehicle’s cooling system is critical. The overheating of your engine causes significant harm, and you must avoid it at all costs. You should begin troubleshooting as quickly as you believe that your...
Top 8 Reasons Why Radiator Fan only Turns on When AC Is on
- Here are a couple of the most likely reasons why your radiator fan will not work otherwise, but only switch on once you turn on the AC. Keep in mind that we’ve written this article catered to the layman so that you can diagnose and troubleshoot on your own without having to rely solely on professional help. You’ll save more money this way. However, before you make a final call on re…
FAQs
- Should The Fan Be on If the Air Conditioner Is Running?
It is most energy-efficient to leave your fan set to AUTO mode. Whenever the system is turned on, does the fan turn on? If your fan is running continuously, moisture has no opportunity to seep outdoors. This recirculates back into your home, where your air conditioner must work overtime … - In What Circumstances Does My Fan Turn on Along with The Air Conditioning?
In this case, the thermostat is not working properly. If the fan and cooling system are operating when they shouldn’t be, there’s a good probability the thermostat needs to be changed. A short circuit or malfunctioning relay switch might have occurred.
Conclusion
- No matter what the issue is, a faulty thermostatic switch, fan resistor or temperature sensor: the good news is that these are all inexpensive parts that you can find and replace on your own, without having to undergo the ordeal of taking your car to a local repair shop and spending big bucks. In no time, you should see your Radiator Fan switching on as the car heats up, regardles…