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Harley Code U1401: Understanding and Troubleshooting the Issue

Chase Manhattan Avatar

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If you own a Harley-Davidson motorcycle, you may occasionally encounter trouble with your bike and see a trouble code on the dashboard. One of the codes you may come across is U1401. This code indicates a communication issue with the body control module (BCM).

When you see the U1401 code, it means that the BCM has lost communication with another module in the onboard diagnostic system. This could be due to a variety of reasons, including wiring issues, a faulty BCM, or problems with the motorcycle’s data bus. The cost of diagnosing and fixing this fault code will depend on the hourly rate charged by the auto repair shop, which typically ranges between $75 and $150 per hour.

To diagnose and fix the U1401 code, you may need to take your Harley-Davidson to a qualified mechanic who has experience with Harley diagnostic trouble codes. They will use a diagnostic tool to read the code and determine the root cause of the problem. Once the issue has been identified, the mechanic will be able to recommend the best course of action to fix the problem.

Understanding Harley Code U1401

Definition and Significance

If you are a Harley-Davidson owner, you may have come across the term “Harley Code U1401.” This code is a diagnostic trouble code (DTC) that is stored in the electronic control module (ECM) of your motorcycle. It indicates that there is an implausible engine speed signal being received by the ECM.

This code is significant because it can cause a number of issues with your motorcycle’s performance. For example, if the ECM receives an implausible engine speed signal, it may not be able to accurately control the fuel injection system or the ignition timing. This can result in poor fuel economy, reduced power, and other performance issues.

Common Symptoms

If your Harley-Davidson motorcycle is displaying the U1401 code, there are a few common symptoms that you may notice. These include:

  • The check engine light may be illuminated on your motorcycle’s instrument panel.
  • Your motorcycle may be running poorly, with reduced power and acceleration.
  • You may notice that your motorcycle is running rough or misfiring.
  • Your motorcycle may be difficult to start or may not start at all.

If you are experiencing any of these symptoms, it is important to have your motorcycle diagnosed and repaired as soon as possible. Continuing to ride your motorcycle with the U1401 code present can cause further damage to your motorcycle and can result in more expensive repairs down the line.

In conclusion, understanding Harley Code U1401 is important for any Harley-Davidson owner. This code indicates that there is an issue with the engine speed signal being received by the ECM, which can cause a number of performance issues. If you are experiencing any of the common symptoms associated with this code, it is important to have your motorcycle diagnosed and repaired as soon as possible.

Diagnostic Trouble Codes Explained

Harley-Davidson motorcycles are equipped with a self-diagnostic system that can detect malfunctions and generate Diagnostic Trouble Codes (DTCs). These codes are alphanumeric and can be read using the trip reset button on your motorcycle. Understanding what these codes mean can help you diagnose and fix any issues your Harley may be experiencing.

Trouble Codes and Harley Models

Each Harley-Davidson model has its own set of trouble codes, and these codes can vary depending on the year and model of your motorcycle. For example, the U0140 and U0142 codes are related to the loss of communication with the body control module, while the P0562 and P1510 codes are related to the battery voltage and throttle control, respectively.

Reading the Codes

To read the DTC codes on your Harley-Davidson, follow these steps:

  1. Turn the ignition switch to the “On” position without starting the engine.
  2. Press and release the trip odometer trigger switch until “diag” appears on the odometer display.
  3. Press and hold the trip odometer trigger switch for five seconds until the “P” codes appear.
  4. Release the trip odometer trigger switch and wait for the “U” codes to appear.
  5. Record the codes and refer to the Harley-Davidson Fault Code Chart to determine what they mean.

It is important to note that while the DTC codes can give you an idea of what is wrong with your motorcycle, they are not always accurate. It is recommended that you use the codes as a starting point for your diagnosis and perform additional tests as needed.

In conclusion, understanding the Diagnostic Trouble Codes on your Harley-Davidson can help you diagnose and fix any issues your motorcycle may be experiencing. By following the steps outlined above, you can read the codes on your Harley and refer to the Fault Code Chart to determine what they mean.

Troubleshooting Electrical Components

If you are experiencing the U1401 code on your Harley Davidson, it is likely due to an issue with one of the electrical components. Here are some steps you can take to troubleshoot and fix the issue.

Ignition System Assessment

Start by checking the ignition system. Make sure the ignition switch and run/stop switch are in the “on” position. Check the LHCM (Left Hand Control Module) and RHCM (Right Hand Control Module) for any signs of damage or wear. If they look fine, move on to the next step.

Battery and Charging System

The U1401 code can also be caused by a problem with the battery or charging system. Check the battery voltage using a multimeter. It should read above 12.2 volts. If it is low, try slow charging the battery for 12 hours and re-test.

Next, start the engine and record the battery voltage on your multimeter. The voltage should be near 14 volts. Raise the engine RPM’s to 2,000 and turn on all your Harley’s electrical accessories, such as lights, radio, etc. The voltage may drop, but should remain near 14 volts during the test.

If the battery and charging system are both functioning properly, the U1401 code may be due to a faulty LHCM or RHCM. In this case, it is best to take your Harley to a professional technician for further diagnosis and repair.

By following these steps, you can troubleshoot and fix the U1401 code on your Harley Davidson. Remember to always take proper safety precautions when working with electrical components.

CAN Bus and Electronic Control Modules

CAN Bus Functionality

The Controller Area Network (CAN) bus is a communication system used in modern Harley-Davidson motorcycles to allow different electronic components to communicate with each other. The CAN bus system enables multiple electronic control modules (ECMs) to communicate with each other over a single wire. This allows for faster and more efficient communication between different components of the motorcycle.

ECM and BCM Issues

The Electronic Control Module (ECM) is a critical component of the Harley-Davidson motorcycle that controls various functions such as fuel injection, ignition, and transmission. The Body Control Module (BCM) is another important component that controls various electrical functions such as lighting and security systems.

If there is an issue with the ECM or BCM, it can cause the U1401 code to appear on your Harley-Davidson motorcycle. This code indicates a loss of communication between the ECM and BCM over the CAN bus system.

One common cause of ECM and BCM issues is a faulty wiring harness. A damaged or corroded wiring harness can cause a loss of communication between the different electronic components of the motorcycle. It is important to regularly inspect the wiring harness and repair or replace any damaged wires.

Another cause of ECM and BCM issues is a faulty component. If a component such as the fuel injector or ignition coil is malfunctioning, it can cause a loss of communication between the ECM and BCM. In this case, the faulty component should be identified and replaced.

In conclusion, the CAN bus system and Electronic Control Modules are critical components of modern Harley-Davidson motorcycles. If there is an issue with the ECM or BCM, it can cause the U1401 code to appear on your motorcycle. Regular maintenance and inspections can help prevent these issues and ensure that your motorcycle is running smoothly.

Sensor-Related Faults and Fixes

If you are experiencing the U1401 code on your Harley, it may be due to a sensor-related fault. Here are some common sensor-related issues that can cause the U1401 code, along with their fixes.

Oxygen Sensors

The oxygen sensors (O2 sensors) are responsible for measuring the amount of oxygen in the exhaust gases. If the O2 sensors are faulty, they can cause the U1401 code to appear. To fix this issue, you may need to replace the faulty O2 sensors.

Throttle Position Sensors

The throttle position sensors (TPS) are responsible for measuring the position of the throttle. If the TPS is faulty, it can cause the U1401 code to appear. To fix this issue, you may need to replace the faulty TPS.

Other sensors that can cause the U1401 code to appear include the intake air temperature (IAT) sensor, engine coolant temperature (ECT) sensor, vehicle speed (VE) sensor, and throttle position sensor (TPS). If you suspect that any of these sensors are faulty, you should have them checked by a professional mechanic.

In addition, there are two specific diagnostic trouble codes (DTCs) that can be related to the U1401 code: P0031 and P0032. These codes indicate a problem with the oxygen sensor heater circuit. If you are experiencing these codes along with the U1401 code, you may need to replace the affected oxygen sensor.

Overall, sensor-related faults can be a common cause of the U1401 code on your Harley. If you suspect that a faulty sensor is causing the issue, it is important to have it checked and replaced if necessary by a qualified mechanic.

Harley-Davidson Specific Error Codes

If you own a Harley-Davidson motorcycle, you may be familiar with the error codes that can appear on your dashboard. One of the codes that you may come across is the U1401 code. This code is related to the secondary communication circuit of your motorcycle.

Code P1510 and P1511

Another error code that you may encounter is the P1510 and P1511 codes. These codes are related to the throttle actuator control system. If you see these codes on your dashboard, it means that there is an issue with the throttle actuator control system. You should take your motorcycle to a qualified technician to have it checked and repaired.

Codes Related to ABS and Horn

If you have an ABS system on your Harley-Davidson motorcycle, you may also come across error codes related to this system. One of the codes that you may see is the P0572 code. This code is related to the brake switch circuit. Another code that you may see is the P0577 code. This code is related to the cruise control switch circuit.

In addition to the ABS system, you may also encounter error codes related to your motorcycle’s horn. If you see the P1510 and P1511 codes, it means that there is an issue with the horn circuit. You should take your motorcycle to a qualified technician to have it checked and repaired.

In summary, there are several error codes that you may encounter on your Harley-Davidson motorcycle. These codes can be related to various systems on your motorcycle, including the secondary communication circuit, throttle actuator control system, ABS system, and horn circuit. If you see any of these codes on your dashboard, it is recommended that you take your motorcycle to a qualified technician to have it checked and repaired.

Repair and Maintenance Tips

Preventive Measures

To avoid the U1401 code and other issues with your Harley-Davidson motorcycle, it’s important to keep up with regular maintenance. This includes changing the oil and filter, checking and replacing spark plugs, and inspecting the brakes and tires. It’s also a good idea to keep your motorcycle clean and dry, and to store it in a dry, covered area when not in use.

In addition to regular maintenance, there are a few preventive measures you can take to reduce the risk of the U1401 code and other issues. One of the most important is to use high-quality fuel and oil, and to avoid using low-quality or contaminated fuel. You should also avoid overloading your motorcycle, and make sure that any accessories or modifications are installed correctly and do not interfere with the operation of the motorcycle.

DIY Versus Professional Help

If you’re experiencing the U1401 code or other issues with your Harley-Davidson motorcycle, you may be wondering whether to try to fix the problem yourself or to seek professional help. While some maintenance and troubleshooting tasks can be done by the average motorcycle owner, others are best left to professionals.

If you’re comfortable with basic maintenance tasks like changing the oil and filter or checking the spark plugs, you may be able to diagnose and fix the U1401 code yourself. However, if you’re not familiar with the inner workings of your motorcycle or if you’re unsure about how to diagnose or fix a problem, it’s best to seek professional help.

A qualified mechanic or Harley-Davidson dealer can provide expert diagnosis and repair services, and can help you avoid making costly mistakes or causing further damage to your motorcycle. They may also be able to provide advice on preventive maintenance and other measures you can take to keep your motorcycle running smoothly.

Remember, maintaining your Harley-Davidson motorcycle is an important part of ownership, and can help you avoid problems like the U1401 code. Whether you choose to do the work yourself or seek professional help, make sure to stay up-to-date on maintenance and troubleshooting tasks to keep your motorcycle in top condition.

Conclusion

In conclusion, the U1401 code is a common problem that Harley-Davidson owners may encounter. It is caused by an implausible engine speed signal and can be diagnosed and fixed within an estimated repair time of 1.0 hour. The cost of repair is influenced by the hourly rate charged by the auto repair shop, which typically ranges between $75 and $150 per hour.

It is important to address this issue promptly to ensure the safety of your motorcycle. Riding with a faulty engine speed signal can lead to further damage to your motorcycle and can even pose a safety risk to you and other motorists on the road.

Regular maintenance of your Harley-Davidson can help prevent issues such as the U1401 code from occurring. It is recommended to follow the manufacturer’s guidelines for maintenance and to have your motorcycle inspected by a professional mechanic on a regular basis.

Overall, the U1401 code is a manageable problem that can be resolved with proper diagnosis and repair. By taking the necessary steps to address this issue, you can ensure the safety and longevity of your Harley-Davidson motorcycle.