P0484 OBD-II Trouble Code: Cooling Fan Circuit Over Current

Our certified mechanics come to you · 12-month, 12,000-mile warranty

SCHEDULE P0484 DIAGNOSTIC Get a fair and transparent estimate upfront
Red-stars EXCELLENT RATING ON

Cost of diagnosing the P0484 code

P0484 is a diagnostic trouble code (DTC) for "Cooling Fan Circuit Over Current". This can happen for multiple reasons and a mechanic needs to diagnose the specific cause for this code to be triggered in your situation. Our certified mobile mechanics can come to your home or office to perform the Check Engine Light diagnostic for $70.00. Once we are able to diagnose the problem, you will be provided with an upfront quote for the recommended fix and receive $30.00 off as a credit towards the repair. All our repairs are backed by our 12-month / 12,000-mile warranty.

Cars Estimate Credit towards follow-up repair Earliest Availability
Ford$70.00$30.00
Toyota$70.00$30.00
BMW$70.00$30.00
SCHEDULE P0484 DIAGNOSTIC Get a fair and transparent estimate upfront

Check Engine Light

Diagnostic Trouble Code (DTC): P0484

P0484 code definition

When the PCM detects a voltage reading from the electric cooling fan control circuit that is either too high or too low in comparison to the manufacturer’s specifications, the P0484 code will be stored.

What the P0484 code means

There are several components that send data to the ECM, allowing it to properly operate the electric cooling fan. This part ensures that the engine temperature does not get too high. If any of the components send data that is more than 10% higher or lower than the manufacturer’s specifications for the current driving conditions, the PCM will store the P0484 code to indicate that there is a malfunction within this circuit.

What causes the P0484 code?

The most common causes behind the P0484 code are a bad cooling fan motor, or a faulty cooling fan relay.

Other causes may include:

If electrical components are shorted or open, there may also be blown fuses.

What are the symptoms of the P0484 code?

Most of the time, only the illuminated Check Engine Light will alert vehicle owners to the presence of the P0484 code; however, the engine may overheat, especially if this code has not been addressed in a timely manner. The air conditioner may also become less efficient at cooling the interior of the vehicle.

How does a mechanic diagnose the P0484 code?

After an OBD-II scanner detects the P0484 code, a technician should begin by inspecting all of the wiring and other electrical components. After repairing or replacing any components that were damaged, loose, corroded, or otherwise inoperable, it is important to clear the code from the PCM, and retest the system. If the code does not return, then the mechanic has diagnosed an electrical issue causing the P0484 code.

If the code does return, the next step is to perform a voltage and ground test on the cooling fan motor and cooling fan relay. Additionally, system fuses should be tested for proper voltage. If any of these parts give a reading that does not align with manufacturer specifications, then that part is likely to blame, and should be replaced.

The next step, should those parts not be faulty, is to diagnose the sensors that provide the ECM with the data necessary to operate the cooling fan. These include the intake air temperature sensor, the A/C refrigerant pressure sensor, the vehicle speed sensor, and the engine coolant temperature sensor. Throughout all diagnostic process, the code should be cleared and the system retested after each attempted repair. This process ensures that no unnecessary repairs are performed.

Common mistakes when diagnosing the P0484 code

Most often, technicians find that a cooling fan motor was replaced in error, when the cooling fan relay was actually to blame. Cooling fan relays are frequently recalled, so it’s important to consider both parts when performing diagnoses on the P0484 code.

How serious is the P0484 code?

If the P0484 code is being detected, the vehicle should be repaired right away. While no symptoms may be observed, an engine that cannot properly monitor engine temperature is likely to need more expensive repairs later on if the issue is not addressed early.

What repairs can fix the P0484 code?

In order to repair the P0484 code, the mechanic may attempt any of the following:

Need help with a P0484 code?

YourMechanic offers certified mobile mechanics who will come to your home or office to diagnose and repair your vehicle. Get a quote and book an appointment online or speak to a service advisor at 1-800-701-6230.

pcm
ECM (Engine Control Module)
trouble codes
Check Engine Light
fans

Fast and easy Check Engine Light is on Inspection service at your home or office.

SCHEDULE P0484 DIAGNOSTIC
Get a fair and transparent estimate upfront

Recent Check Engine Light is on Inspection reviews

Excellent Rating


YourMechanic Check Engine Light is on Inspection Service

Average Rating

4.5/5

Number of Reviews

3,936

Rating Summary
3,597
169
44
25
101
3,597
169
44
25
101

Robert

17 years of experience
436 reviews
Robert
17 years of experience
Robert is excellent at what he does and is a very knowledgeable mechanic.
2016 JEEP GRAND CHEROKEE - CHECK ENGINE LIGHT IS ON - DENVER, COLORADO

Sam

12 years of experience
62 reviews
Sam
12 years of experience
Very professional and thorough. He was on time with no issue and dove right into the diagnosis. Very appreciated.
2016 CHRYSLER 200 - CHECK ENGINE LIGHT IS ON - OKLAHOMA CITY, OKLAHOMA

Kinder

18 years of experience
40 reviews
Kinder
18 years of experience
Great technician patiently explained malfunction of an old Dodge truck was prompt and punctual, repaired truck in about 45 minutes I would recommend Kinder Mike R
1998 DODGE RAM 1500 - CHECK ENGINE LIGHT IS ON - DOUGLASVILLE, GEORGIA

Peter

33 years of experience
346 reviews
Peter
33 years of experience
2001 HONDA ODYSSEY - CHECK ENGINE LIGHT IS ON - SAN DIEGO, CALIFORNIA

More related articles

Insurance Requirements for Car Registration in Kentucky
The Kentucky Transportation Cabinet requires that all drivers in Kentucky carry liability automotive insurance, or “financial responsibility” in order to operate a vehicle legally and maintain vehicle...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...
How to Get a Louisiana Driver's Permit
s licensing program. The first step in this program is to obtain...

Related questions

Q: Abs, brake lights are on, and the check engine light is on. Code PO500 came up. I changed our speed sensor on the back axle as well.

There could be a wiring issue with the vehicle speed sensor from the computer to the speed sensor pigtail. If the wiring is good, then the PCM may not correctly configured for the actual tire size on the vehicle. If...

Q: The engine keeps shutting off and rpms slowly drop to zero

Hello. If the RPMs drop off right as the engine is stalling then the most common cause of this is a bad crankshaft position sensor. This sensor tells the engine computer what the engine RPM speed is and what...

Q: Crank but not start, There is spark and fuel spray in injector, I change the PCM and distributor box but still the same no start

If you are getting spark and fuel to the engine then the only thing left to check is the compression in the engine. Have a compression test done to see if the timing belt may have jumped timing. You should...

How can we help?

Our service team is available 7 days a week, Monday - Friday from 6 AM to 5 PM PST, Saturday - Sunday 7 AM - 4 PM PST.

1-800-701-6230 · hi@yourmechanic.com