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Harley Code B1337: Understanding the Brake Light Switch Circuit

by

Chase Manhattan

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Owner and Editor at The Wrench Network

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Hey y’all, it’s Chase Manhattan! I’m a life-long automotive and motorcycle enthusiast with a knack for diagnostics that I hope to share with you! Lately, I’ve been running my own motorcycle rental business, which you can read about here, and it has been a great experience that has allowed me to own numerous bikes that I probably couldn’t justify otherwise. Plus, it’s been a great way to experience new places while on vacation. If you haven’t heard of them before, I definitely recommend checking out the Riders-Share platform if you get the itch to ride while away from home, or if you want to explore a cheaper way to own and ride motorcycles!

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If you own a Harley-Davidson motorcycle and are experiencing issues with your front left speaker, you may have encountered error code B1337. This code indicates that the front left speaker is shorted together. While this may seem like a daunting issue, there are steps you can take to diagnose and potentially fix the problem.

First, it is important to understand that error code B1337 is specific to Harley-Davidson motorcycles and is part of the Diagnostic Trouble Code (DTC) system. This system is designed to help you identify issues with your motorcycle by generating alphanumeric codes when it detects a malfunction in one or more sensors, circuits, or components.

To diagnose the issue with your front left speaker, you can use the onboard diagnostic system (OBD) on your Harley-Davidson motorcycle. This system allows you to read the DTC codes and determine the root cause of the problem. Once you have identified the issue, you can take steps to fix the problem yourself or take your motorcycle to a professional mechanic for repair.

Understanding Harley Code B1337

If you’re experiencing issues with your Harley-Davidson and have received DTC B1337, this section will help you understand what it means and what symptoms you may be experiencing.

Significance of DTC B1337

DTC B1337 stands for “Door Ajar Right Rear Circuit Short To Battery”. This code is typically caused by a short circuit in the wiring of the right rear door ajar switch. When this switch is activated, it sends a signal to the body control module (BCM) to let it know that the door is open. If there is a short circuit in the wiring, the BCM may receive a signal indicating that the door is open even when it is not. This can cause a number of issues, including draining the battery and causing the interior lights to stay on.

Common Symptoms

If you have received DTC B1337, you may be experiencing one or more of the following symptoms:

  • Interior lights staying on even when the door is closed
  • Battery draining quickly
  • Door ajar warning light staying on even when the door is closed

If you are experiencing any of these symptoms, it is important to have your Harley-Davidson inspected by a qualified technician as soon as possible. They will be able to diagnose the issue and recommend the appropriate repairs.

In conclusion, DTC B1337 indicates a short circuit in the wiring of the right rear door ajar switch. If you are experiencing symptoms such as interior lights staying on or the battery draining quickly, it is important to have your Harley-Davidson inspected by a qualified technician.

Diagnostic Procedures

If you have a Harley-Davidson motorcycle and are experiencing trouble with the front left speaker, the B1337 diagnostic trouble code (DTC) may have been triggered. This DTC indicates that the front left speaker has shorted together. Here are some diagnostic procedures you can follow to troubleshoot this issue.

Initial Diagnostic Steps

The first step in diagnosing the B1337 DTC is to check the speaker wiring and connections. Make sure that the wiring is not damaged or frayed, and that the connections are secure and free of corrosion. You can also check the speaker itself by using a multimeter to test its resistance.

If the wiring and connections are in good condition and the speaker tests okay, the next step is to check the speaker output on the electronic control module (ECM). Use a diagnostic tool to read the DTCs stored in the ECM, and check for any other related codes. If the ECM is not functioning properly, it may need to be replaced.

Advanced Troubleshooting Techniques

If the initial diagnostic steps do not resolve the issue, you may need to use more advanced troubleshooting techniques. One option is to perform a system reset by disconnecting the battery for a few minutes, then reconnecting it and starting the motorcycle. This can sometimes clear the DTC and resolve the problem.

Another option is to perform a more thorough diagnostic procedure using a diagnostic tool. This tool can read the live data from the ECM and help pinpoint the source of the problem. You can also use the tool to perform specific tests on the speaker and wiring to check for resistance and continuity.

In conclusion, if you are experiencing trouble with the front left speaker on your Harley-Davidson motorcycle and have received the B1337 DTC, there are several diagnostic procedures you can follow to troubleshoot the issue. By checking the wiring and connections, testing the speaker, and using a diagnostic tool, you can identify and resolve the problem quickly and effectively.

Electrical System Insights

If you are experiencing a B1337 code on your Harley-Davidson, it’s important to understand the electrical system that is involved in this fault. This code is related to the Body Control Module (BCM), which is responsible for managing various systems within your motorcycle. Let’s take a closer look at the electrical system and the components involved.

Battery and Ignition System

The battery and ignition system are critical components of your Harley-Davidson motorcycle. The battery provides the power needed to start the engine and run the electrical systems. The ignition system provides the spark that ignites the fuel in the engine. If either of these systems is not functioning properly, it can cause a B1337 code to appear.

To ensure that your battery and ignition system are functioning properly, it’s important to perform regular maintenance. This includes checking the battery voltage and ensuring that the terminals are clean and tight. You should also check the ignition switch and wiring to ensure that there are no loose connections or damaged wires.

Body Control Module (BCM)

The Body Control Module (BCM) is responsible for managing various systems within your Harley-Davidson motorcycle, including the lighting, instrument panel, and security system. If the BCM is not functioning properly, it can cause a B1337 code to appear.

To diagnose the issue with the BCM, you will need to use a diagnostic tool to read the fault codes. Once you have identified the issue, you can then take the appropriate steps to repair or replace the faulty component. It’s important to note that the BCM is a complex system and should only be repaired by a qualified technician.

In summary, a B1337 code on your Harley-Davidson motorcycle is related to the Body Control Module (BCM) and can be caused by issues with the battery, ignition system, or BCM itself. By performing regular maintenance and working with a qualified technician, you can ensure that your motorcycle is running smoothly and free of fault codes.

Harley-Davidson Control Modules

Harley-Davidson motorcycles are equipped with several control modules that help to manage various functions of the bike. These modules are responsible for managing the engine, transmission, braking system, and other functions. The two primary control modules on a Harley-Davidson motorcycle are the Left Hand Control Module (LHCM) and the Right Hand Control Module (RHCM).

LHCM and RHCM Functions

The LHCM controls the functions of the left-hand side of the handlebar, including the turn signal, horn, and high beam switch. The RHCM controls the functions of the right-hand side of the handlebar, including the starter, kill switch, and engine run switch. Both control modules communicate with each other via the Controller Area Network (CAN) bus, which allows them to share information and work together to manage the bike’s functions.

Control Module Error Codes

If there is an issue with one of the control modules, it may trigger a diagnostic trouble code (DTC). One such code is B1337, which indicates a fault with the front left speaker. This code is associated with the LHCM and can be caused by a short circuit in the speaker or a problem with the LHCM itself.

Other control module error codes include internal errors, which can be caused by a malfunction in the module’s software or hardware. LHCM and RHCM internal errors can cause a variety of issues, including problems with the bike’s lighting system and issues with the starter or engine run switch.

If you encounter any of these error codes, it is recommended that you take your Harley-Davidson motorcycle to a certified technician for diagnosis and repair. They will have the tools and expertise necessary to accurately diagnose and fix the issue, ensuring that your bike is running smoothly and safely.

Motorcycle Communication Networks

When it comes to modern motorcycles, communication networks play a crucial role in the functioning of various systems. Harley-Davidson, like many other manufacturers, uses a Controller Area Network (CAN) bus system to facilitate communication between various electronic control modules (ECMs) in the bike.

CAN Bus System

The CAN bus is a two-wire communication protocol that enables real-time data transmission between different modules. In a Harley-Davidson motorcycle, the Body Control Module (BCM) is responsible for managing the CAN bus system. The BCM receives and sends signals to various modules, including the Engine Control Module (ECM), Radio, and Speedometer.

Troubleshooting CAN Bus Issues

In case of a fault in the CAN bus system, it can be challenging to identify the root cause of the problem. However, Harley-Davidson has a comprehensive set of Diagnostic Trouble Codes (DTCs) that can help you pinpoint the issue.

If you encounter code B1337, it means that the front left speaker is shorted together. This issue can arise due to a faulty speaker or wiring problems. To diagnose and fix the issue, you should check the wiring connections and test the speaker for continuity.

In case the issue persists, you should consult a Harley-Davidson dealership or a certified mechanic. They can use specialized diagnostic tools to identify the problem and fix it.

In conclusion, understanding the CAN bus system and troubleshooting its issues is crucial for maintaining the proper functioning of your Harley-Davidson motorcycle. By following the manufacturer’s guidelines and seeking professional help when needed, you can ensure that your bike runs smoothly for years to come.

Sensor and Switch Diagnostics

If you’re experiencing trouble with code B1337 on your Harley, it’s likely that you’re dealing with a shorted front left speaker. However, it’s important to perform a thorough diagnostic check to rule out any other issues. In this section, we’ll cover two important sensors and switches that you should check to ensure they’re functioning properly: the oxygen sensor and IAT, and the run/stop switch.

Oxygen Sensor and IAT

The oxygen sensor and IAT (intake air temperature) are both critical components of your Harley’s engine control system. The oxygen sensor measures the amount of oxygen in the exhaust gases, which is used to determine the air/fuel ratio. The IAT measures the temperature of the air entering the engine, which is used to adjust the fuel injection timing.

If either of these sensors is malfunctioning, it can cause a variety of issues with your Harley’s performance. To check the oxygen sensor, you’ll need to use a multimeter to measure the voltage and resistance. You should also inspect the wiring and connectors for any signs of damage or corrosion. To check the IAT, you can use a scan tool to read the temperature values. If the values are outside of the normal range, it may indicate a problem with the sensor.

Run/Stop Switch Functionality

The run/stop switch is another important component of your Harley’s electrical system. It’s responsible for controlling the flow of power to the ignition system and other components. If the switch is malfunctioning, it can cause a variety of issues with your Harley’s performance, including stalling, misfiring, and difficulty starting.

To check the run/stop switch, you’ll need to use a multimeter to measure the voltage and resistance. You should also inspect the wiring and connectors for any signs of damage or corrosion. If the switch is faulty, it will need to be replaced to restore proper functionality.

By checking these sensors and switches, you can ensure that your Harley’s engine control system is functioning properly. If you’re still experiencing trouble after checking these components, it may be necessary to perform a more in-depth diagnostic check.

Audio System Challenges

If you are experiencing issues with your Harley-Davidson’s audio system, the B1337 code may be the culprit. This code indicates that the front left speaker is shorted together, which can cause a range of problems with your sound system.

Radio and Speaker Errors

When your front left speaker is shorted together, it can cause the audio from your radio to sound distorted or completely cut out. You may also notice that the volume is lower than usual or that the sound only comes from one side of the bike.

In addition to the front left speaker, the B1337 code can also indicate issues with the rear left speaker. If you are experiencing problems with both speakers, it is important to troubleshoot the entire audio system to determine the root cause of the problem.

Troubleshooting the Audio System

To troubleshoot the audio system, start by checking the wiring and connections for both the front and rear left speakers. Make sure that all wires are securely connected and that there are no signs of damage or wear.

If the wiring and connections are in good condition, the next step is to check the speakers themselves. Use a multimeter to test for continuity and resistance, and replace any speakers that are not functioning properly.

If you are still experiencing issues with your audio system after checking the wiring and speakers, it may be necessary to bring your bike to a professional mechanic or dealership for further diagnosis and repair.

Overall, the B1337 code can be a frustrating issue to deal with, but with proper troubleshooting and repair, you can get your Harley-Davidson’s audio system back up and running smoothly.

Preventive Measures and Maintenance

Harley code B1337 is related to the front left speaker being shorted together. This issue can be frustrating, but there are some preventive measures you can take to avoid it. Here are some tips to help you maintain your Harley Davidson and prevent this code from appearing.

  • Regular Maintenance: Regular maintenance is essential to keep your bike running smoothly. It includes checking the wiring and connections to ensure they are clean and tight. Make sure you follow the maintenance schedule in your owner’s manual to avoid any issues.

  • Battery Voltage: A low battery voltage can cause BCM problems, including code B1337. Check the battery voltage and make sure it’s at least 12.5 volts. If the battery voltage is low, charge or replace the battery.

  • Fuses: Check the fuses for the BCM and make sure they’re not blown. If you find any blown fuses, replace them immediately.

  • Speaker Wiring: Check the wiring for the front left speaker and make sure it is not damaged. If you find any damaged wiring, replace it immediately.

  • Upgraded Speakers: If you are experiencing this code frequently, consider upgrading your speakers to avoid the issue altogether. Upgraded speakers can improve the performance of your bike and provide a better sound quality.

By following these preventive measures and maintaining your Harley Davidson regularly, you can avoid code B1337 and other BCM related issues. Remember, preventive maintenance is the key to keeping your bike running smoothly and ensuring optimal performance.

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