P1479 Transmission Fan Relay Circuit Open Or Shorted

A P1479 Transmission Fan Relay Circuit Open or Shorted indicates a fault in the transmission fan relay circuit. The most common causes of this code are an open or shorted condition in the transmission fan relay, wiring issues such as poor connection, corrosion, and/or damaged wires, or faulty relays within the system. Other potential causes include low battery voltage due to a weak battery or alternator failure; defective PCM; and faulty transmission fan motor.

The most common cause of this code is a faulty ground connection or wiring issue between the fan motor and the relay circuit. It could also be caused by damaged parts such as failing relays or connectors, which need to be replaced. In some cases, it could even indicate a bad fuse or blown relay switch on either side of the connector leading from the fan motor to its power source.

P1479 Transmission Fan Relay Circuit Open Or Shorted

Radiator Fan

Radiator fans are a vital component of any vehicle’s cooling system, and it is important to understand how they work in order to keep your car running smoothly. A radiator fan is responsible for pushing air through the radiator, allowing heat to be dissipated from the engine so that it does not overheat and cause damage.

When the temperature of an engine rises above a certain level, usually around 200 degrees Fahrenheit, a thermostat will open up and allow coolant to flow into the engine block.

As this liquid passes through it absorbs heat before exiting back out via hoses connected to the radiator where fans help push air across its surface allowing further dissipation of that heat. Most modern cars have two fans; one which runs constantly when your car has been turned on (the primary fan), and another which only turns on once temperatures reach a certain threshold (the secondary fan).

The primary fan keeps airflow going at all times, even when idling or stopped at traffic lights; while the secondary kicks in as needed when extra cooling is required during hot summer days or after periods of hard driving such as long journeys with heavy loads.

Also Read: How to Diagnose P1283 Idle Select Signal Invalid in Your Vehicle

Cooling Fans

Cooling fans come in a variety of shapes and sizes that can be used for everything from circulating air throughout a room to providing direct relief from hot temperatures.

In this post, we’ll take an in-depth look at how these devices work, the types available on the market today, and some tips for shopping around when looking for one that best suits your needs. At their core, cooling fans are simply machines that generate airflow by moving air across an area using blades or propellers.

The direction and speed of these blades create a force known as thrust which pulls cooler air toward you while pushing out hot air away from you – creating an environment where you feel more comfortable due to reduced heat levels.

This makes them very useful not only during warmer times but also when attempting to reduce humidity levels inside certain rooms like bathrooms or kitchens; no matter what climate you live in, having a quality fan can help keep temperatures bearable year-round!

Radiator Fan Replacement Cost

The average cost for replacing a radiator fan in the United States ranges from $150-$400 depending on the make and model of the car you drive and whether you choose to have a licensed mechanic do the job or if you plan on doing it yourself.

The main components that will affect the overall price include parts (fan assembly), labor time (if applicable), and any additional extras like antifreeze refills or other fluids. Additionally, there may be slight differences in costs between different makes/models due to variations in design complexity and installation requirements.

P1479 Transmission Fan Relay Circuit Open Or Shorted

What Symptoms Can Be Seen When P1479 Transmission Fan Relay Circuit is Open Or Shorted

It is important to understand the symptoms of an open or shorted P1479 Transmission Fan Relay Circuit in order to properly diagnose and repair your vehicle.

The P1479 code is a generic trouble code indicating that there is an issue with the transmission fan relay circuit, which helps regulate cooling for the automatic transmission system. This can include any potential issues with wiring, connectors, relays, and fuses associated with this circuit.

When this code appears, it indicates that either the fan relay circuit has been opened or shorted out due to some kind of electrical fault. As such, one of the most common symptoms you’ll notice when your P1479 Transmission Fan Relay Circuit is open or shorted will be a decrease in performance from your car’s engine and transmission systems because they are not receiving as adequate cooling as they should be.

You may also notice a decrease in fuel efficiency as well as increased strain on other components due to a lack of proper cooling.

Additionally, higher-than-normal operating temperatures could lead to accelerated wear and tear on these parts leading them to fail early if left unchecked over time.

Symptoms of a P1479 Transmission Fan Relay Circuit Being Open Or Shorted Include Engine Stalling, Lack of Power, And/Or No Fuel Economy Gains

If you’re experiencing engine stalling, lack of power, and/or no fuel economy gains in your vehicle, it could be an indication that the P1479 Transmission Fan Relay Circuit is open or shorted. The P1479 code is a generic OBD-II trouble code indicating a problem with the transmission fan relay circuit. It can also be referred to as “transmission fan control circuit high voltage” or simply “TFC circuit high voltage.”

A faulty transmission fan relay can cause severe damage to the entire driveline if not addressed quickly enough. When this code appears on your vehicle’s computer system, it indicates that the ECU has detected too much voltage flowing through the TFC (Transmission Fan Control) relay circuit.

This means that there may be an issue with one of several components within this system including wiring harnesses, relays, connectors, solenoids, and other related items such as fuses and sensors.

All these components are vital for controlling how much oil flows through your vehicle’s transmission when shifting gears or accelerating from a stop position – so any failure here will lead to significant issues over time.

How Can I Check If My Vehicle Has a Faulty P1479 Transmission Fan Relay Circuit

If you suspect that your vehicle may have a faulty P1479 Transmission Fan Relay Circuit, it is important to properly diagnose the issue as soon as possible. A faulty transmission fan relay circuit can cause several issues with your vehicle, such as a lack of power or poor fuel economy. In order to check for this fault, there are certain steps you will need to take.

The first step in diagnosing whether or not your vehicle has a faulty P1479 Transmission Fan Relay Circuit is to inspect the wiring harnesses connected to the relay circuit.

If any of these wires appear worn or frayed, they should be replaced immediately before continuing any further diagnostics. Additionally, if you notice any corrosion on the terminals where these wires connect, this should also be addressed and cleaned up prior to testing anything else.

Once all connections look good and no visible damage can be seen on the wiring harnesses connected to the relay circuit, then it’s time to move on to actually testing for faults in the system itself.

You Will Need to Use an Obd-Ii Scanner to Read the Trouble Codes on Your Vehicle And See If There are Any Codes for the Transmission Fan Relay Circuit That May Indicate an Issue With It Being Either Open Or Shorted Out

The transmission fan relay circuit is an important component of your vehicle, as it helps to regulate the temperature of the transmission system. Without it, your car can overheat and cause some serious damage to its components. If you think there may be an issue with this circuit, then using an OBD-II scanner is a great way to find out what’s wrong.

An OBD-II scanner is a diagnostic tool that plugs into the On-Board Diagnostics (OBD) port on vehicles produced after 1996. It’s used to read trouble codes from the vehicle’s computer and help diagnose any issues with its systems. When plugged in, it will display any trouble codes stored in the engine control unit (ECU), including those related to malfunctioning or shorted-out circuits such as the transmission fan relay circuit.

What Other Components Could Be Affected by a Faulty P1479 Transmission Fan Relay Circuit

If you have been experiencing issues with your vehicle’s P1479 transmission fan relay circuit, it could be indicative of a larger underlying problem. Many other components in the system may be affected by this issue and need to be inspected or replaced as well. The first component that can be affected by a faulty P1479 transmission fan relay circuit is the Transmission Control Module (TCM).

The TCM is responsible for controlling various aspects of the transmission such as gear selection, torque converter lockup, and shift points. If there is an issue with the P1479 circuit, then it can cause communication problems between the PCM and TCM leading to incorrect shifting behavior or even complete failure of gear engagement.

In addition to these electronic components, mechanical components inside the transmission can also suffer due to issues with this particular relay circuit.

One example is if there isn’t enough coolant flow through the system due to a failing cooling fan motor or overheating caused by lack of air circulation from not having proper ventilation from outside sources like radiators or fans.

This could lead to excessive wear on internal clutch packs resulting in slipping gears during operation which would ultimately affect vehicle performance.

A Faulty Transmission Fan Relay Circuit Can Affect the Operation of Other Components in the System Such As the Alternator, Starter Motor, And Transmission Solenoid Valve among Others Which Rely on This Component Working Properly in Order to Function Optimally

When a vehicle’s transmission fan relay circuit malfunctions, it can cause serious issues for the entire system that relies on its operation. This component is responsible for controlling the flow of electrical power to other components in the transmission system such as the alternator, starter motor, and transmission solenoid valve.

If there is an issue with this component then these parts will not be able to function optimally and may even fail completely.

A faulty fan relay circuit can manifest itself in several ways including poor engine performance or a noticeable increase in noise coming from inside the car when idling or driving at low speeds. It can also cause problems with shifting gears as well as stalling out while running which are all symptoms of an underlying relay issue within the system.

MINI: Erratic Idle Issue, SOLVED


If your car is having issues with its transmission fan relay, this blog post is for you. It explains the basics of what a transmission fan relay does, why it can cause problems if it’s open or shorted out, and how to go about diagnosing and fixing the issue. The discussion covers common symptoms that indicate an open or shorted circuit such as erratic shifting or poor engine performance at higher RPMs.

It also provides tips on testing the circuit itself and replacing any damaged components. Finally, there are some general maintenance recommendations to help ensure this problem doesn’t recur in the future. All in all, this post should give you a better understanding of P1479 transmission fan relays and provide guidance on how to identify potential faults quickly so they can be resolved before further damage occurs.