Cooling fans are an integral part of a vehicle’s cooling system. A relay, which is a type of electromagnetic switch, controls the power supply sent to each of the cooling fans. There is usually one relay for each fan or fan speed. If your vehicle’s powertrain control module (PCM) detects a problem with the cooling fan control circuit, it may trigger the P0481 code.
Diagnostic trouble code (DTC) P0481 stands for “ Fan 2 Control Circuit.” It is important to note that most platforms don’t have this trouble code in their library. It only appears on certain vehicles, so you might not ever see this code even if your vehicle has one or more cooling fans.
Cooling fan relays control the power supplied to your engine’s cooling fans. If the engine temperature reaches a point that’s considered unsafe, the PCM will command one of the cooling fan relays to activate one of the fans. The exact temperature threshold depends on your vehicle’s year, make, and model. Some GM cooling fans (like on the late ‘90s Chevy Cavalier) don’t activate until the engine coolant goes as high as 228 degrees.
The code P0481 may be triggered when the PCM detects that the command and the result do not match when it activates the number two cooling fan relay. The algorithms vary. Some systems will have a circuit monitoring the fan output to determine whether the relay is delivering power when switching is commanded. Note that similar trouble codes like P0480 and P0482 may also register due to a defective cooling fan relay.
Read our discussion about different cooling fan configurations for more information that can help you understand what to do with OBD codes like P0481.
Note: The definition of code P0481 code may be different per vehicle manufacturer. Consult the appropriate repair manual or repair database for the exact code definition.
DTC P0481 is a generic trouble code that can appear in various makes and models. While the symptoms and triggers for this trouble code may be similar across several automakers, the diagnosis and repair steps may vary depending on the vehicle.
If you’re not an experienced automotive DIYer, we recommend taking your vehicle to an auto repair shop for proper diagnosis and repair. If you’d want to fix the issue yourself, consider reviewing this video for additional information about this trouble code:
Fixing a P0481 code isn’t easy, especially if you don’t have the tools and experience to get the job done, so we strongly recommend leaving the job to a trusted professional. But if you’re an experienced DIYer, feel free to deal with the code yourself. Consult a repair manual or repair database for vehicle-specific repair steps.
Electric cooling fans initially appeared on front wheel drive vehicles with transversely mounted (east-west) engines because the belts and pulleys were on the side of the engine and the radiator remained in the front of the vehicle.
Typically, there will be either one or two cooling fans depending on the platform, shape of the radiator, and whether or not the vehicle is equipped with air conditioning, which just about every vehicle has nowadays.
Some early electric cooling fans were hardwired to power or ground and had a thermo-switch in the radiator that would close the circuit to activate the fan. One example of this design was found on early VW Rabbits, but the radiator fan switches on those vehicles tended to fail quite often.
The smarter way to control an electric cooling fan is to have a thermostatic switch or a module wired to close a relay, which is far less likely to fail due to the rather significant current required by cooling fan motors.
Eventually, to remove the belt-driven fan load from the engine, electric fans became more common even on rear wheel drive vehicles with north-south mounted engines. Some vehicles, like later model Jeep Cherokees, have a belt driven fan and an electric fan that would be engaged by the PCM if the A/C high side pressure rises too high.
Another arrangement that is fairly common since the early 2000s is the electrically variable viscous coupling belt driven fan, where the fan speed and activity is controlled by the ECM/PCM but the fan is still belt driven. Chevy Trailblazers and some Ford Explorers are equipped with this kind of fan control.
If you have a faulty cooling fan assembly, it’s best to stop driving your vehicle until you replace it. Engine issues cost a lot to repair, so you want to prevent additional damage that might happen if the fan stops working correctly. Fortunately, the replacement cooling fan assemblies at CarParts.com can save you money without skimping on quality.
At CarParts.com, you can get world-class cooling fan assemblies at lower prices. Our products are competitively priced, so you can get your vehicle back on the road without exceeding your budget. We also make it easy to find the part you need. Put the year, make, model, and engine of your car or truck in our website’s built-in selector, and choose the cooling fan assembly that fits your vehicle. Our products ship from a nearby distribution center, ensuring your new part gets to you in a few business days.
Replace your faulty cooling fan assembly before it completely fails. Check out our wide array of reliable cooling fan assemblies and shop now at CarParts.com.
Any information provided on this Website is for informational purposes only and is not intended to replace consultation with a professional mechanic. The accuracy and timeliness of the information may change from the time of publication.