Have you been having problems with the blower motor on your car? You may need to bypass the blower motor resistor if this is the case. Our goal in this article is to provide step-by-step instructions on how to bypass blower motor resistor in order to get it working again.
The wiring harness needs to be unplugged from the blower motor resistor in order to bypass a blower motor resistor. In this way, the fan motor will be able to run at full power without being constrained by the resistor. You can learn more about the process on how to bypass blower motor resistor and what you need to do to ensure a successful bypass by reading on.
What Is a Blower Motor Resistor?
An actual blower motor switch is the switch or button on the dash that you use to boost or decrease the blower motor’s speed. A fan is the only one that powers the blower motor. Rather than simply stopping and restarting, the blower motor can operate at a variety of speeds thanks to the resistor. The blower motor cannot regulate the fan speed when a resistor fails in the blower motor. In this case, the fan will only operate at its maximum speed, and it will not allow the air to escape.
Blower motor problems can indicated by fluctuating fan speed or running out blower motor resistors. An HVAC system uses a blower motor resistor to control the speed of the blower motor and prevent overheating. Replacing the resistor is not necessary if you know the problem is not due to the resistor. It is best to replace the resistor if you notice any of the above symptoms.
What Does The Blower Motor Resistor Connect To?
It is traditional to ground and wire the resistor in series with the blower motor assembly when using blower motors. Controlled by a resistor that differs in resistance from blower motor to blower motor. This controls the current flowing through the blower motor.
Resistors located close to the air cabin filter are easy to replace because they are simple to replace. If the resistor is faulty, the blower will only run at one speed with the HVAC controls and not at any other speed. There is a blower motor resistor behind the glove compartment or at the bottom of the HVAC housing. It may be necessary to use tools to remove the glove box on some vehicles, but it may not be necessary in others.
To remove the resistor, the wiring harness must disconnected and the screws removed. The garage is a good place to store your blower motor if it is not functioning in the middle of summer. If you don’t want to invest in new equipment, here are some easy steps to replace a blower motor. By using the FIXD Sensor and app, you can monitor the health of your car at all times.
It may caused by corrosion or overheating when your blower motor resistor fails. Motor current controlled by the resistor, which is a mechanical device. Overheating and failure of the resistor may result if the resistor is overrun. During certain conditions, the fuse on the resistor board may blow, resulting in a reduction in blower speed. In the event that the resistor fuse blows, your car will continue to run at high speeds, but it will need to replaced.
Where Is The Resistor Located In Blower Motor?
Usually, the heater blower motor resistor located underneath the dashboard. Within the compartments of the heater and air conditioner, it can found. An air conditioning system device controls the blower motor fan.
An electrical component resistor (also called a blower motor resistor) can prevent current flow into the blower fan. Fans can sped up or slowed down using this feature. Slower rotation of the fan causes less air to circulate throughout the cabin, which reduces resistance. A faulty blower motor resistor will result in heat loss and air loss in your automotive HVAC system. To replace a good one, here are some suggestions.
In the open circuit, the Ohmmeter registers infinity, which indicates the blower resistor needs to be replaced. In this way, the system will remain more uniform, and a cause may even be discovered.
Can You Bypass A Blower Motor Resistor?
An electronic blower motor resistor regulates the motor’s speed through an electronic control system. As well as the blower motor and the control switch, the resistor connected in series with them. Control switches control the voltage applied to blower motors. By changing the resistance in the circuit, the blower motor resistor controls the speed of the blower motor. In most cases, the resistor locates near the blower motor in the air duct.
So how to bypass blower motor resistor? Actually it won’t be difficult to bypass the blower motor resistor. There are a few steps involved in replacing the resistor, in addition to finding and disconnecting it. It is important to have a resistor in the cooling system. The amount of current flowing through the motor can control its speed. An automobile’s climate control system includes a blower motor resistor. A blower motor’s speed is controlled by this device by controlling the flow of current through it. Additionally to regulating the air temperature in the vehicle, it determines the speed at which it circulates.
What are the Signs of a Bad Blower Motor Resistor?
Although they are pretty darn reliable, blower motor resistors can go bad without much warning. The good news is that a blower motor resistor can diagnosed fairly easily.
A bad blower motor resistor can identified by some of the following signs:
- Inability to control HVAC fans (all or certain speeds)
- Only the highest speed setting works on the fan
- There is no air coming from the vents
- A fan that runs intermittently or inconsistently
According to our story above, you’ll likely first notice the problem when the passenger cabin in your vehicle doesn’t cool down or heat up as it normally would-which brings us to an important point. In addition to affecting your HVAC system’s ability to heat up and cool down, a bad blower motor resistor directly affects airflow.
How to Bypass Blower Motor Resistor?
Resistors on blower motors can fail and need to replaced in some cases. The blower motor can become noisy and cause reduced air flow. It is necessary to bypass the blower motor resistor in order to solve this problem. So how to bypass blower motor resistor?
Finding the blower motor resistor is the first step in bypassing it. The rectangular shape of this component can identified on the firewall of a vehicle. The rectangular shape of this component can identified on the firewall of a vehicle.
After installing the bypass wire, the next step is to connect it to the power supply. The positive terminal of this wire should be connected to the positive terminal of the blower motor, and the negative terminal should connected to the negative terminal. When this done, the blower motor will be able to operate at its full speed since the resistor will bypassed. Lets learn all the method on how to bypass blower motor resistor.
Method 1: Direct Wiring
Bypassing the blower motor resistor, direct wiring connects the blower motor directly to the power source. Manually adjusting the power supply to the motor allows you to control the fan speed.
Step-by-step guide
Follow these steps to bypass the blower motor resistor using direct wiring:
- Remove the wiring harness: Carefully remove what found near the blower motor itself or in the HVAC system’s ductwork.
- Disconnect the wiring harness: Disconnect the wires connecting the blower motor to the resistor.
- Power and ground wires: Locate the power and ground wires connected to the blower motor. If necessary, refer to the wiring diagram for your vehicle.
- Cutting and stripping the wires: Use wire cutters/strippers to cut the wires leading to the blower motor resistor. To expose the wire conductors, remove a small portion of insulation from the cut ends.
- Connect the power and ground wires: Connect a 12V power source directly to the blower motor’s power wire, such as the battery’s positive terminal. A suitable ground point, such as the vehicle chassis, should connected to the ground wire.
- Insulate the connections: Cover each wire connection with electrical tape as a short-circuit protection measure.
Pros and cons of the direct wiring method
The advantages and limitations of direct wiring are as follows:
Pros:
- Bypass method that is simple
- Directly controls the speed of the blower motor
- Resistor replacement is a cost-effective alternative
Cons:
- For desired fan speed, the power supply may need to be manually adjusted
- If operated at high speeds for extended periods, it can strain the blower motor
- It does not provide the original functionality of the blower motor resistor, such as automatic speed adjustment based on temperature
Method 2: Using a Bypass Harness
Using a bypass harness, the blower motor is directly connected to the power source, bypassing the blower motor resistor. As a result, the bypass process has simplified, and the connection has been made more organized and secure.
Installation process
You can bypass the blower motor resistor by installing a bypass harness as follows:
- Make sure you purchase a bypass harness that is compatible with the make and model of your vehicle.
- To prevent any electrical mishaps during installation, disconnect the vehicle’s battery.
- Identify the blower motor resistor. The blower motor resistor is usually located near the blower motor or inside the ductwork of the HVAC system.
- Carefully disconnect the wiring harness that connects the blower motor resistor to the vehicle’s electrical system.
- Through the wiring harness previously attached to the resistor, connect the bypass harness to the blower motor.
- Make sure all connections are secure and properly seated. Any additional steps or recommendations should followed according to the manufacturer’s instructions.
- To restore power to the vehicle’s electrical system, reconnect the vehicle’s battery once the bypass harness has installed.
Pros and cons of using a bypass harness
There are several benefits and considerations to using a bypass harness:
Pros:
- Provides a plug-and-play bypass solution that simplifies the bypass process
- Minimizes the risk of electrical problems by ensuring secure and reliable connections
- Makes it easier to remove and reinstall if necessary
- Ensures that the electrical system of the vehicle maintains its original integrity
Cons:
- For your specific vehicle, you will need to purchase a compatible bypass harness
- Compared to other bypass methods, this may be a more expensive solution
- Specific vehicle models may not have harnesses readily available
Method 3: Installing a Resistor Pack
You can also bypass the blower motor resistor by installing a resistor pack. A new group of resistors substituted for the faulty one, providing a fixed resistance value. By using the resistor pack, the speed of the blower motor can be properly regulated.
Locate the resistor in the blower motor of the HVAC system to begin. Identify the faulty resistor and disconnect the wiring harness. Removing the resistor from its mounting location and noting its original location is the first step.
The new resistor pack should now aligned correctly in the mounting location. Make sure the connections on the pack match those on the wiring harness. Be careful not to damage any surrounding components when installing the resistor pack.
Connect the wiring harness to the resistor pack once the resistor pack has been securely installed. Make sure the blower motor is working as it should. With the new resistor pack installed, the blower motor speed should be effectively controlled.
There are pros and cons to using a Resistor Pack to bypass a faulty blower motor resistor. Let’s examine them in more detail:
Pros and Cons of Installing a Resistor Pack
Pros:
- The resistor pack ensures adequate regulation of the blower motor speed by providing a fixed resistance value. In this way, the cabin airflow can maintained.
- Specific vehicle models are compatible with resistor packs, which ensure a seamless fit and electrical compatibility. As a result, compatibility issues during installation reduced.
- Compared to more complex methods such as modifying the wiring harness, installing a resistor pack is relatively straightforward. Many vehicle owners can do this project themselves with basic automotive knowledge and the right instructions.
- By removing the resistor pack and reinstalling the original resistor, you can return to the original blower motor resistor configuration. By doing this, flexibility provided as well as the ability to switch back if necessary.
Cons:
- Specific vehicle models may require different resistor packs, so they may not be universally applicable. To avoid compatibility issues, make sure the resistor packs you purchase are compatible with your vehicle’s make and model.
- In spite of the fact that a resistor pack regulates blower motor speed, it does not entirely bypass the resistor. There is still some resistance in the circuit due to the pack acting as a resistor. It may affect the blower motor’s overall functionality in some cases.
- A resistor pack costs more than a jumper wire, which is a more straightforward method. There can be a wide range of prices for resistor packs based on their brand and quality, as they are typically aftermarket components.
- If a resistor pack installed on the vehicle, the warranty provided by the manufacturer may voided. Check the warranty terms and conditions before proceeding with this method to avoid potential problems.
Method 4: Installing a Variable Speed Controller
A Variable speed controllers allow you to adjust and control the speed of the blower motor. The fan speed can be precisely controlled by installing a variable speed controller instead of bypassing the blower motor resistor.
Step-by-step instructions
Here are the steps to bypass the blower motor resistor with a variable speed controller:
- Your vehicle’s blower motor and electrical system should fitted with the appropriate variable speed controller. Take into account factors like compatibility, installation ease, and features available.
- Before installing the battery, disconnect it as a precautionary measure to avoid electrical accidents.
- You can find the blower motor resistor inside the HVAC system’s ductwork or near the motor.
- Carefully disconnect the wiring harness that connects the blower motor resistor to the vehicle’s electrical system.
- The variable speed controller must connected according to the manufacturer’s instructions. In most cases, the controller connected to the blower motor via the wiring harness that was previously attached to the resistor.
- Make sure all connections are properly seated and secured. Make sure to check the manufacturer’s instructions for any additional steps or recommendations.
- Connect the vehicle’s battery after installing the variable speed controller to restore power to the electrical system.
Pros and Cons
There are several benefits and considerations to using a variable speed controller:
Pros:
- It allows you to adjust the fan speed precisely according to your comfort needs
- Maintains the original wiring integrity of the vehicle’s electrical system
- Reduces blower motor strain by allowing gradual speed adjustments
- Provides automatic fan speed adjustment based on temperature settings, if supported by the controller
Cons:
- This requires the purchase of a variable speed controller compatible with the blower motor on your vehicle
- A controller’s features and specifications may require additional wiring and adjustments during installation
- Variable speed control adds functionality to this bypass method, making it more expensive than other bypass methods
When you understand the precautions, methods, and considerations involved with bypassing the blower motor resistor, you will be confident in using these techniques to regain control over your vehicle’s HVAC system. Always prioritize safety, follow the manufacturer’s instructions, and seek professional assistance if you have any questions. Bypassing the blower motor resistor will provide you with a comfortable and efficient ventilation experience.
How to Troubleshoot a Blower Motor Resistor Bypass?
Several steps can be taken in order to troubleshoot the bypass if it does not seem to work correctly. Check the connections to make sure they are all properly connected. As soon as the connections made, the fuse should checked. For the blower motor to work again, the fuse must replaced if it has blown.
What are the Benefits of Bypassing the Blower Motor Resistor?
- There are several advantages to bypassing the blower motor resistor. It allows you to regain control over the fan speed, ensuring optimal comfort inside your vehicle.
- In addition, it eliminates the need for a potentially expensive resistor replacement.
- Furthermore, bypassing the resistor can provide a temporary fix if a replacement part is unavailable.
Replacing the Blower Motor Resistor
In the event that the bypass is not successful, the blower motor resistor may need to replaced. A new resistor can installed in place of the old one after the old one has removed. Ensure that the new resistor is the same type and size as the old one so that it will fit correctly.
How Do You Replace Your Blower Motor Resistor?
This guide outlines how to replace a faulty blower motor resistor.
- Identify the blower motor resistor
Find out where the resistor for the blower motor is located. The battery is usually found beneath the dash or in the engine compartment on the passenger side. The blower motor is close to it.
- Remove the motor resistor from the blower
Make sure the AC pigtail and cooling duct are disconnected from the components surrounding the blower motor resistor. The blower motor resistor can removed by ratcheting loose the bolts holding it in place. Removing the blower motor resistor is as easy as removing the bolts.
- Remove all wires from the device
The wires attached to the blower motor resistor should cut once the resistor has been removed. Wire strippers or scissors can used to cut the wires.
- Remove the old blower motor resistor and install the new one
Before continuing installation, apply dielectric grease to the housing of the blower motor resistor. By doing this, you will keep water out, a problem that is common when driving off-road. To protect the component, apply a coating to the plastic.
Put the blower motor resistor back where it belongs. Finish the job by tightening the screws and connecting the pigtail.
A pigtail may also worn out if it has already used for some time. If this is the case, proceed to the next step.
- Attach the pigtail to the wire
Reconnect the new wires after disconnecting the worn-out ones. This should be relatively straightforward since most cables are color-coded. The new wires should connected to the connections. You have completed the task by returning the pigtail to its original position.
Preventing Further Damage
Following the replacement or bypass of the blower motor resistor, steps must taken to prevent further damage. It is possible to do this by checking the air filter and replacing it if necessary. Moreover, the wiring may need to checked for damage or corrosion and repaired or replaced if necessary.
Conclusion: How to bypass blower motor resistor?
Now you have some idea on how to bypass blower motor resistor. A viable solution to restoring HVAC system functionality is to bypass the blower motor resistor. The long-term effects on the blower motor’s performance should be considered when weighing the benefits and limitations of each method. It is crucial that installation be done properly, safety precautions are adhered to, and legal regulations are followed.
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FAQs
How safe is it to bypass the blower motor resistor?
Bypassing the resistor can provide a temporary solution, but long-term use is not recommended. When left unchecked, this can lead to overheating or damage to the blower motor.
Is it possible to bypass the blower motor resistor?
By bypassing the resistor, the power source is usually directly connected to the blower motor. Wires can be connected or a resistor bypass harness can be used if available.
Do I need any tools or materials to bypass the resistor?
There may be a need for wire cutters, wire strippers, electrical tape, and a jumper wire as a power source. It depends on the make and model of your vehicle what tools you will need.
If the resistor fails, can I replace it with a higher-rated resistor?
The use of a resistor with a higher rating isn’t recommended since it may affect your HVAC system’s performance and cause overheating.
Is it safe to drive with a bypassed blower motor resistor?
Until the faulty resistor can be replaced, bypassing the resistor should only be considered as a temporary solution. It is not recommended to use the bypass for an extended period of time as it can lead to other issues.