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Harley Code P2122: Understanding the Throttle/Pedal Position Sensor/Switch ‘D’ Circuit Low

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If you own a Harley-Davidson motorcycle, you may have encountered the dreaded check engine light. One of the fault codes that could trigger this warning is P2122. This code indicates a problem with the throttle position sensor (TPS) or twist grip sensor (TGS) circuit. When this happens, the engine may not perform as expected, and you may experience reduced power or other issues.

The P2122 code is a low circuit code, which means that the TPS or TGS is not providing the expected voltage to the engine control module (ECM). This could be due to a wiring issue, a faulty sensor, or other problems. In some cases, the issue may be intermittent, which can make it difficult to diagnose. If you ignore this code, it could lead to more serious problems with your engine or other components.

Fortunately, there are steps you can take to diagnose and fix the P2122 code. Depending on the root cause of the problem, you may be able to resolve the issue on your own or with the help of a mechanic. In this article, we’ll explore the common causes of the P2122 code, the symptoms you may notice, and the steps you can take to fix the problem. With this information, you can get back on the road with confidence and avoid costly repairs down the line.

Understanding Code P2122

If you’re a Harley-Davidson owner and have encountered the P2122 fault code, it’s important to understand what it means and how to address it. This code is related to the throttle position sensor (TPS) and indicates that the on-board computer has detected low voltage in the sensor.

What Is Code P2122

Code P2122 is a diagnostic trouble code that is triggered when the TPS sends a low voltage signal to the vehicle’s computer. This can be caused by a variety of issues, including loose or faulty wiring, a damaged sensor, or a problem with the throttle control system.

Symptoms of Code P2122

There are several symptoms that you may experience if your Harley-Davidson is displaying the P2122 fault code. These can include:

  • Reduced engine power
  • Rough idling or stalling
  • Difficulty accelerating
  • Reduced fuel efficiency

If you notice any of these symptoms, it’s important to have your vehicle inspected by a qualified mechanic as soon as possible. Ignoring the problem can lead to further damage to your engine and potentially costly repairs.

In some cases, the P2122 code may be accompanied by other throttle-related codes, such as P1510 or P2138. These codes can provide additional information about the underlying issue and should also be addressed by a professional technician.

In conclusion, the P2122 fault code is a serious issue that should not be ignored. If you’re experiencing any symptoms related to this code, you should have your vehicle inspected by a qualified mechanic as soon as possible to prevent further damage to your engine.

Diagnostic Steps

If you encounter the P2122 code on your Harley, don’t panic. Here are some diagnostic steps you can take to identify the problem:

Initial Code Reading

First, you need to read the code using an OBD-II scanner. This will give you an idea of what’s causing the issue. The P2122 code indicates that there is a low circuit in the throttle/pedal position sensor/switch.

Sensor and Circuit Inspection

The next step is to inspect the sensor and circuit. Start by checking the wiring harness for any damage or loose connections. If everything looks good, test the voltage going into the sensor. It should be around 5 volts. If the voltage is off, there may be a problem with the power supply to the sensor.

If the wiring and voltage check out, you may need to replace the throttle position sensor. This is a relatively simple fix that you can do yourself. Just make sure to clear the code using the OBD-II scanner after replacing the sensor.

In summary, the P2122 code on your Harley indicates a problem with the throttle/pedal position sensor/switch. To diagnose the issue, you need to read the code using an OBD-II scanner and inspect the sensor and circuit. If everything checks out, you may need to replace the sensor.

Troubleshooting Electrical Components

If you’re experiencing Harley code P2122, it’s important to troubleshoot the electrical components of your motorcycle. Here are some steps you can take to diagnose and fix the problem.

Checking the TPS

The throttle position sensor (TPS) is a critical component in your motorcycle’s electrical system. It’s responsible for sending signals to the engine control module (ECM) that help regulate the fuel injection system. If the TPS is malfunctioning, it can cause the P2122 code to appear.

To check the TPS, you’ll need a multimeter. First, disconnect the TPS connector and turn on the ignition switch. Then, measure the voltage between the TPS sensor ground wire and the 5-volt reference wire. The voltage should be between 4.5 and 5 volts. If the voltage is low, you may need to replace the TPS.

Inspecting Wiring and Connectors

Damaged wiring or faulty connectors can also cause the P2122 code to appear. To inspect the wiring and connectors, start by visually inspecting the wiring for any signs of damage, such as frayed wires or loose connections. If you find any damage, replace the wiring or connector as needed.

Next, use a multimeter to test the continuity of the wiring and connectors. Set the multimeter to the continuity setting and touch the probes to each end of the wiring or connector. If you don’t get a reading, the wiring or connector may be faulty.

Finally, check the ground wire for any signs of damage or corrosion. A faulty ground wire can cause the ECM to detect low voltage in the TPS, triggering the P2122 code. If you find any damage or corrosion, replace the ground wire.

By following these steps, you can troubleshoot the electrical components of your motorcycle and diagnose the cause of the P2122 code. Remember to always wear protective gear and follow proper safety procedures when working on your motorcycle’s electrical system.

Throttle System Repairs

If you are experiencing Harley code P2122, it is likely that you are dealing with an issue in your throttle control system. Fortunately, there are a few common repairs that can help you address the problem.

Throttle Actuator Motor Issues

One possible cause of P2122 is a problem with the throttle actuator motor. This component is responsible for controlling the opening and closing of the throttle valve, which regulates the flow of air into the engine. If the actuator motor is not functioning properly, it can cause issues with the throttle position sensor, leading to a P2122 fault code.

To repair a faulty throttle actuator motor, you may need to replace the component entirely. This can be a complex repair, so it is recommended that you seek the assistance of a qualified technician. However, if you are comfortable working on your Harley yourself, you can consult your service manual for instructions on how to replace the throttle actuator motor.

Pedal Position Sensor Faults

Another potential cause of P2122 is a problem with the pedal position sensor. This component is responsible for detecting the position of the accelerator pedal, which helps to regulate the throttle position. If the sensor is not functioning properly, it can cause issues with the throttle control system, leading to a P2122 fault code.

To repair a faulty pedal position sensor, you may need to replace the component entirely. This can be a complex repair, so it is recommended that you seek the assistance of a qualified technician. However, if you are comfortable working on your Harley yourself, you can consult your service manual for instructions on how to replace the pedal position sensor.

In summary, if you are experiencing Harley code P2122, it is likely that you are dealing with an issue in your throttle control system. By addressing common issues with the throttle actuator motor and pedal position sensor, you can resolve the problem and get back to enjoying your ride.

PCM and Electrical Issues

When it comes to the P2122 code on a Harley Davidson motorcycle, there are a few potential causes that riders should be aware of. One of the most common causes of this code is related to the Powertrain Control Module (PCM) and electrical issues. In this section, we’ll take a closer look at some of the most common issues related to the PCM and electrical system that could cause the P2122 code to appear.

Powertrain Control Module Errors

One of the most common causes of the P2122 code is related to errors with the Powertrain Control Module (PCM). The PCM is responsible for controlling the engine and transmission functions in your Harley Davidson motorcycle. If there is an issue with the PCM, it could cause the P2122 code to appear.

One potential issue with the PCM is related to errors in the EEPROM memory. The EEPROM memory is responsible for storing data related to the engine and transmission functions. If there is an error in the EEPROM memory, it could cause the P2122 code to appear.

Voltage and Ground Problems

Another potential cause of the P2122 code is related to voltage and ground problems in the electrical system. The ECM voltage and grounds are critical for the proper functioning of the engine and transmission systems. If there is an issue with the voltage or ground, it could cause the P2122 code to appear.

One potential issue with the voltage and ground is related to errors in the flash memory. The flash memory is responsible for storing data related to the engine and transmission functions. If there is an error in the flash memory, it could cause the P2122 code to appear.

In conclusion, when it comes to the P2122 code on a Harley Davidson motorcycle, there are a few potential causes that riders should be aware of. Issues related to the PCM and electrical system are some of the most common causes of this code. By understanding these potential causes, riders can take steps to diagnose and repair the issue, ensuring that their motorcycle is running smoothly and efficiently.

Clearing the Code P2122

If you have received the code P2122 on your Harley Davidson, it means that there is an issue with the twist grip sensor. This could be due to loose or faulty wiring, or a bad sensor. To fix this issue, you will need to clear the code and reset the check engine light. Here’s how you can do it:

Resetting the Check Engine Light

  1. The first step is to clear the code. You can do this by using a scan tool or code reader. Connect the tool to the OBD-II port under the dashboard and follow the instructions on the tool to clear the code.

  2. Once the code has been cleared, you will need to reset the check engine light. This can be done by disconnecting the battery for a few minutes. Make sure to disconnect the negative terminal first, and then the positive terminal.

  3. After a few minutes, reconnect the battery by connecting the positive terminal first, and then the negative terminal. This will reset the check engine light.

  4. Start your Harley Davidson and check if the code has been cleared. If the code is still present, it may be a pending code. A pending code means that the issue has not been resolved yet, and the code will reappear after a certain number of driving cycles.

  5. If the code is still present, you will need to diagnose the issue further. Check the wiring and connections for any damage or corrosion. You may also need to replace the twist grip sensor if it is faulty.

By following these steps, you can clear the code P2122 and reset the check engine light on your Harley Davidson. Make sure to diagnose the issue properly to prevent the code from reappearing in the future.

When to Visit a Dealer

If you have received a P2122 diagnostic trouble code on your Harley, you may be wondering if it is time to visit a dealer. While it is possible to diagnose and fix this issue on your own, there are some situations where visiting a dealer is the best course of action.

Dealer-Specific Diagnostic Tools

One reason to visit a dealer is that they have access to dealer-specific diagnostic tools that can help pinpoint the exact cause of the P2122 code. These tools can provide more detailed information than generic OBD-II scanners, which can save you time and money in the long run.

Additionally, if the P2122 code is related to a TGS 2 A/D validation error or a BCM issue, the dealer will have the specialized knowledge and expertise to diagnose and fix the issue correctly. Attempting to fix these issues on your own can be risky, as you may end up causing further damage to your Harley.

In summary, if you are experiencing issues related to the P2122 code and are unsure of how to proceed, it is best to visit a dealer. They have the specialized tools and knowledge needed to diagnose and fix the issue correctly, which can save you time and money in the long run.

Preventive Measures and Maintenance

To prevent the occurrence of Harley code P2122, it is important to perform regular maintenance on your motorcycle. This includes checking the battery and cables for any signs of wear or damage. A weak or faulty battery can cause electrical problems, including issues with the throttle or pedal position sensor/switch.

Regularly inspecting the throttle/pedal position sensor/switch is also important. Look for any signs of damage, such as cracks or corrosion. If you notice any issues, it is best to replace the sensor/switch to prevent further problems.

In addition to regular maintenance, it is important to handle your motorcycle with care. Avoid harsh acceleration or sudden stops, as this can cause damage to the throttle/pedal position sensor/switch. It is also important to avoid exposing your motorcycle to extreme temperatures or weather conditions.

If you do experience Harley code P2122, it is important to address the issue as soon as possible. Ignoring the problem can cause further damage to your motorcycle and potentially lead to more expensive repairs.

Overall, by performing regular maintenance and handling your motorcycle with care, you can help prevent the occurrence of Harley code P2122 and keep your motorcycle running smoothly.