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The signal wire at the fan will be the shortest of the three wires. Connect a 12 volt test light to battery +, turn on the ac, and then probe the wire. You can tell the fan is getting a signal if the test light turns on.
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I reinstalled it in my vehicle and began testing it with a voltmeter.
On the fan’s red wire, I read that there is a constant 12 volt supply. That being the case, mine does not.
There is signal on the signal wire. I think I saw. at the signal wire, 05 volts. Again, since it is only a signal, there cannot be much voltage. Probably 05 is plenty to turn it on.
My red wire from the harness to the + terminal by the motor has no continuity. Additionally, there is no continuity between the + side of the 40w fuse and the red harness wire (+). (I believe its fuse 88)
Additionally, I do this even when the car is running or with the ignition on. Nothing has changed.
I know the fan needs to be operating because the coolant temperatures are halfway up. Even my AC is on full blast (AC should turn my cooling fan on as well)
It was my hunch. Find the relay; I suspect that’s the problem. It appears that the only item left to test is this.
I located the cooling system’s wiring diagram. I can see the relay, but I’m not sure where it is. It might be under the pass seat, according to something I read. I looked, but there is nothing there.
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relay, but if everything is working, it might/might not be the coolant temperature switch, which would prevent the fan from turning on even though the fan would be good.
I have a brand-new spare coolant temperature switch in my toolbox, which is kind of funny. However, because the fan is supposed to receive constant 12v and the remote wire is what instructs it to turn it on, I fail to see why it wouldn’t supply 12v.
Problem addressed when a failed radiator fan was replaced and picked up a few days later!
I drove it to my brother-in-house law’s with an OBDII reader attached up to monitor temperatures more closely. There were no problems on the interstate. In order to make sure everything was in order, I let it idle in the driveway. Temperatures begin to rise. Never turns on the radiator fan. At the first overheat alert at roughly 231 degrees, I turned it off.
Returning to the shop, they replaced a fan relay under the passenger footwell, tested everything, and it didn’t overheat. They were incredibly sorry and committed to fix the problem. I take it and park it in my driveway to idle. Temperatures begin to rise, the radiator fan never turns on, and I turn it off when the first overheat alert appears, at about 231 degrees. Sigh.
Return to the store (even more apologetic and determined to resolve the issue)… When they rechecked the fan circuit, they discovered a contact that had overheated at the back fuse carrier, close to the battery. They believe that the (old) fan’s high draw was the root of the problem. They established the contact again, and everything proceeded as planned.
The Upcoming Steps
There is no need to freak out if you find an issue with your cooling fans. It’s crucial that you stop as soon as the temperature gauge needle starts to go into the red. The longer you drive, the longer your engine will have to heat up, and the more issues your car will experience.
Once your car has cooled off, you can look inside to verify if the cooling fan is functioning properly. You can connect jumper wires to the negative and positive terminals of your car battery, respectively. Utilize the opposite side of the fan motor’s connections. Exercise cautious because the blades on these motors are very sharp. If the fan motor is not functioning, a replacement is required. Additional issues could arise with the cooling fan, fuse, or temperature switch.
BMW-North
Kind of – The e46 e-fan can record the DME controlled PWM signal. Unfortunately, unlike in later models, the fan in the e46 arrangement only provides live RPM feedback at starting, thus you must presume that the PWM signal being transmitted via the Bosch interpreter corresponds to the right speed. Prior to live logging, you can check this (the PWM signal to speed ratio) by doing a quick INPA fan test to make sure PWM signals affect RPMS.
For a better understanding of the interrelationships, see the short sample log below where the speed of the BMW water-pump, fan, and t-stat opening was being watched (recorded). Although it was available, I regret not including e-fan RPM in my log (the focus was the electric water pump on later BMWs). The “Requested Speed” is the PWM signal, and the “Actual Speed” is the e-fan RPM. On more recent models, DME performs better because it checks for live deviations on most PWM-using components, including the fan. Monitoring these variations is crucial for the more recent electric water pumps.
How is the cooling fan of a BMW x3 checked?
Turn on your air conditioner to quickly test your fan; it should turn on. If it doesn’t, it might be broken. The fan should run on HIGH if you unhook your coolant temperature sensor. Keep in mind that using this method will result in the setting of a fault code that must be cleared.
How do you use a multimeter to test a radiator fan?
You must therefore check the voltage of a few fuses in the under-dash fuse box (numbers 3, 15, and 20) and under-hood fuse box in order to determine whether the radiator fan is functioning (number 47 and 50). Start the car or set the ignition key to position II (IG2). Given that you will be testing 12V circuits, set the multimeter’s meter to “20” in the DCV section.
The negative battery terminal (for under-hood fuses) or a metal ground point on the vehicle will receive the black multimeter probe (for under-dash fuses). Each fuse has two contacts where test probes from a multimeter must be touched in order to obtain readings.
Take a reading by placing the red probe on one of the two contacts. The amount must be close to 12 volts. There is no need to worry about accurately capturing the voltage reading because it varies depending on a number of things, including the output of the alternator and the charge in the battery. Take the reading by touching the robe to another contact.
12V on each of the contacts. It signifies the fuse is in good working order, so you can just check the next one.
One contact has 12V, and the other has 0V. This is a blown fuse’s telltale indicator. You must swap it out.
Both contacts have 0V. It indicates that there is no power to the fuse, which is only conceivable if the black probe is improperly grounded to a metal object or linked to the battery’s negative terminal. To take readings, detach the probe and then re-connect it.
How can I test my battery-connected radiator fan?
Here is one strategy to consider if you want a blog titled “How to connect an electric fan to a battery”:
Connect one end of the second jumper wire to the positive wire coming from the fan. Connect the jumper wire’s other end to the battery’s positive terminal. The fan should turn on when the cable comes into contact with the battery’s positive terminal.
It really is that easy! The fan should turn on immediately if you make sure to connect its positive wire to the battery’s positive terminal. Whether you’re attempting to beat the heat or simply want your clothes to dry more quickly, this is a terrific method to obtain cooling breeze when you need it.
How can I tell if the radiator fan is functioning properly?
Start your car’s engine and crank the air conditioner to its highest setting to see if the radiator fan is operating. The fan’s spinning indicates that the wiring, relay, fuse, and fan motor are all in good working order.
This test’s one flaw is that it doesn’t reveal whether the coolant temperature sensor, temperature switch, or ECU powers the fan when the temperature rises to dangerous levels.
In some vehicles, the fan speed is changeable. The ECU decides how frequently and at what speed to run the fan based on data from a variety of sensors. If any of these inputs are flawed, the PCM will receive inaccurate data. The fan will thus receive incorrect instructions from the PCM regarding when and how fast to turn on.
In this situation, you need to make sure your sensors are operating properly. On your dash, a check engine light will also appear if one or more of these sensors is faulty. It’s time to troubleshoot, according to this light.
How is a radiator fan troubleshooted?
Checking the fuses should be your first step if your radiator fan won’t turn. For the fan itself, there will be a sizable fuse that you should inspect. It will typically be a bigger fuse positioned in the engine compartment and will have a current rating of between 30 and 50 amps. However, you need to consult your owner’s manual to learn the precise location for your particular automobile model.
In most car types, there will also be one or more smaller fuses for the radiator fan control module or relay. You must once more look in the instruction manual for the position of these fuses. You might also find these fuses inside the vehicle.
If you discover a blown fuse, you might want to look at the wiring and try to determine why. A blown fuse, though, could occasionally only be a short-term issue.
How is a system fan tested?
- Install and download SpeedFan.
- Launch SpeedFan and give it some time to gather data.
- Look over the data displayed in the main application window.
- Compare the CPU fan’s RPM data to the recommended RPM range in the manual or specs sheet by checking the RPM data for it.
How can I tell if the radiator fan relay is malfunctioning?
engine overheating A hot-running or overheating engine is one of the initial signs that a cooling fan relay is malfunctioning or defective. The relay may not be working properly if you find that your engine is operating at higher temperatures than usual.
Can I drive a car with a broken radiator fan?
Although driving without a radiator fan is technically possible, it is never recommended. The performance of your vehicle’s cooling system is essential, and every time your engine overheats, harm results.
What type of sensor activates the radiator fan?
The cooling system fuse should be located there, according to your car’s owner’s manual. The mechanic must immediately replace the fuse if it has failed.
The Engine Control Unit (ECU), which receives a signal from the Coolant Temperature Sensor, controls the cooling fan on the majority of contemporary automobiles.
If it’s broken, the fan won’t run when it should, which could cause the engine to overheat.
The cooling fan’s power is managed by the fan relay. The fan will be impacted if the relay has a problem.
Wiring issues could be at fault. The mechanic will examine the fan’s wiring to ensure that it is all correctly connected and operating.
A new motor will need to be installed if the motor that drives the fan is broken.
Verify the amount of engine coolant. Your cooling fan will have to work harder to maintain a normal engine temperature if your engine coolant level is too low.
Locate the coolant expansion tank in the engine bay and check the level there. It often has two marks—a minimum and a maximum level mark. Always keep the coolant level between these two markers.