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Harley Davidson Throttle By Wire Problems? Help Is Here!

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Ever left stranded by sudden Harley throttle problems, with your beast of a machine rendered a whimpering invalid by an unexpected throttle by wire failure? The gut-churning disappointment is hard to bear for the hardcore Harley enthusiast. Fear not. You’ve landed in the right place to unravel the mysteries of Harley Davidson’s throttle by wire issues. We navigate the complicated technical terrain, simplify the jargon, and put the power back in your hands — literally. By examining every hiccup and breakdown, offering hands-on solutions, we are here to ensure there’s nothing standing between you and the open road. So strap in, tighten your grip and get ready to throttle your worries away!

What Are Common Harley Davidson Throttle By Wire Problems?

The Throttle By Wire system, also known as electronic throttle control, has replaced the traditional mechanical throttle cables with electronic sensors and actuators. The system is designed to provide more precise, immediate response to rider input, resulting in smoother and quicker acceleration. However, as innovative as this system is, it’s not immune to technical glitches.

Clogged Throttle

A clogged throttle in Harley Davidson motorcycles often results from accumulated dust, debris, or corrosion. This can hinder the smooth operation of the throttle, leading to performance issues. To address this, start by inspecting the throttle body for any physical obstructions or signs of dirt and grime. Use a specialized throttle body cleaner and a soft brush to gently clean the area. Ensure that all moving parts are well-lubricated to prevent future clogging. Regular maintenance and cleaning of the throttle area can significantly reduce the risk of clogging.

Throttle Fails to Close

One of the common issues that riders have reported is that the throttle fails to close when released. Unlike traditional motorcycles where the throttle snaps back to its resting position when let go, a malfunctioning TBW system fails to do so, causing safety concerns.

Unresponsive Throttle

Another common problem is an unresponsive throttle. There have been instances where riders have reported a complete loss of throttle response while riding, leading to a sudden loss of power.

Faulty Throttle Position Sensor (TPS)

The Throttle Position Sensor (TPS), a critical part of the TBW system, can also cause issues. A faulty TPS can lead to incorrect signals being sent to the Electronic Control Module (ECM), resulting in poor engine performance, stalling, or difficulty starting the bike.

Entering Modes Unexpectedly

In some cases, due to sensor issues, the TBW system may force the motorcycle into different modes, such as the limited performance mode, power management mode, or forced shutdown mode, which can significantly affect the bike’s performance.

How Do You Diagnose Throttle By Wire Issues in Harley Davidsons?

Diagnosing TBW issues requires a systematic approach. The diagnosis should start by checking for any error codes. Harley Davidson motorcycles are designed to display diagnostic error codes when the system encounters a problem.

  • Check for Diagnostic Error Codes: The error code can provide a clue to the origin of the problem. If an error code related to the TBW system is displayed, it can indicate where the problem lies.
  • Inspect the Throttle Grip Sensor: The throttle grip sensor, consisting of two sets of magnetic sensors, sends signals to the ECM. If either of these signals is lost, the ECM will put the motorcycle into limited performance mode. If both signals are lost, the ECM will go into forced idle mode.
  • Examine the Throttle Control Actuator: The actuator, which includes a geared permanent magnet DC motor and two sealed throttle position sensors, plays a crucial role in the TBW system. If the DC motor or one or both of the throttle position sensors are lost, the ECM will put the bike into “limp mode”, limiting the motor to only an idle.
  • Check the Throttle Position Sensor (TPS): If you notice poor acceleration, decreased fuel efficiency, or engine idling and stalling, you should check the TPS. If it’s faulty, the best solution would be to replace it.

Error Codes That Tip You Off

Many times with an electronic throttle, your bike’s ECU will trigger a DTC (diagnostic trouble code) to alert you of the problem. Here are a few codes that are common when dealing with electronic throttle control issues:

Error Code P2135

  • Explanation: This code indicates a problem with the Throttle/Pedal Position Sensor/Switch ‘A’/’B’ Voltage Correlation. It suggests an inconsistency in the signals from the throttle position sensors, potentially leading to erratic throttle behavior.
  • Expansion: In your article, explain how to diagnose this issue, such as checking the sensor connections and testing sensor output with a multimeter. Offer guidance on recalibrating or replacing the sensors if needed.

Error Code P1511

  • Explanation: This code is related to the Throttle Actuator Control Power Management. It usually appears when the ECU detects a significant discrepancy in the throttle operation, potentially triggering a safety mode to prevent damage.
  • Expansion: Discuss common causes, like wiring issues or sensor malfunctions. Provide step-by-step troubleshooting, including how to inspect and test the throttle actuator and related wiring.

Error Code U1040

  • Explanation: This code signifies a loss of communication with the ECM/PCM. It can be due to various issues, including faulty wiring, bad connections, or ECM problems.
  • Expansion: Offer advice on checking the motorcycle’s electrical system, including ECM connections and continuity tests for potential wiring issues. Suggest consulting a professional if the problem persists, as ECM issues can be complex.

Can Throttle By Wire Problems Affect Riding Safety on a Harley?

Yes, issues with the TBW system can significantly affect riding safety on a Harley. For instance, if the throttle fails to close when released, it can lead to uncontrollable acceleration, posing a serious safety risk. Similarly, an unresponsive throttle can lead to a sudden loss of power while riding, which can be dangerous, especially at high speeds.

What Are the Symptoms of Throttle By Wire Failure in a Harley?

The symptoms of TBW failure in a Harley can range from subtle to obvious. These include:

  • Sudden Loss of Power: This is the most common symptom of a TBW issue. The rider may experience a sudden loss of power, usually when the throttle is opened.
  • Unresponsive Throttle: The rider may find that the throttle is unresponsive. This can manifest as poor acceleration, surging, jerking, or hesitation when accelerating or revving up and down with no response from the accelerator.
  • Entering Modes Unexpectedly: The motorcycle may unexpectedly enter different modes, such as the limited performance mode, power management mode, or forced shutdown mode.
  • Engine Stalling: The engine may stall or have difficulty starting, indicating a potential problem with the TPS.

How to Fix Throttle By Wire Problems in Harley Davidson Bikes?

Fixing TBW problems involves identifying the specific issue and addressing it appropriately. Here’s a rundown of possible solutions:

  • Throttle Fails to Close: Adjust the throttle cables to ensure proper functionality. Inspect and clean all electrical components related to the TBW system to prevent corrosion.
  • Unresponsive Throttle: Check for loose wiring and reconnect it if needed. If the throttle is still unresponsive, check if the TPS has the correct setting. Reset it or replace it if necessary.
  • Faulty Throttle Position Sensor: If you determine a faulty TPS, the best solution will be to replace the sensor.
  • Entering Modes Unexpectedly: Check your Harley throttle actuator to see if it is positioned correctly. Replace it if it’s contaminated. Also, check the grip sensor and brake sensor if the error codes persist. Replace any faulty sensors.

LIMP Mode Overview and How To Reset It

is designed to protect the bike’s engine and the rider in case of significant malfunctions, particularly in the throttle by wire (TBW) system. When activated, LIMP mode restricts the bike’s performance, limiting speed and power to prevent further damage or loss of control.

  • Faulty sensors, such as the Throttle Position Sensor (TPS) or grip sensors.
  • Discrepancies in throttle operation or electronic signals.
  • System errors indicated by specific diagnostic codes.
  1. Turn Off the Engine: Start by switching off your motorcycle completely. This allows the system to reset any temporary errors.
  2. Check for Error Codes: Before attempting a reset, diagnose any error codes using a diagnostic tool. This helps identify the underlying issue causing LIMP mode.
  3. Address the Root Cause: If a specific error code or malfunction is identified (like a faulty TPS), address this issue first. This may involve replacing sensors or repairing wiring.
  4. Resetting the System: After resolving the underlying issue, reset the TBW system. Turn the ignition to the ‘on’ position without starting the engine. Slowly rotate the throttle to its fully open and closed positions several times. This process recalibrates the throttle system.
  5. Restart the Engine: Finally, turn off the ignition and then restart the engine. Check if the motorcycle exits LIMP mode and returns to normal operation.

Are Throttle By Wire Issues Common in Certain Harley Models?

There isn’t any substantial evidence to suggest that TBW issues are more common in specific Harley Davidson models. However, it’s worth noting that the TBW system was introduced in Harley Davidson motorcycles from 2008 onwards. Therefore, models manufactured during and after 2008 that feature the TBW system may encounter such issues.

What Causes Throttle By Wire Malfunctions in Harley Davidsons?

Several factors can lead to TBW malfunctions in Harley Davidsons:

  • Faulty Sensors: The TBW system relies heavily on sensors to function correctly. If any sensor, such as the throttle grip sensor or TPS, malfunctions, it can disrupt the operation of the TBW system.
  • Corrosion or Dirt: Accumulation of dirt, debris, or grime around the throttle grip can hinder the smooth operation of the throttle. Similarly, corrosion can damage the electronic components, leading to malfunctions.
  • Wiring Issues: Damaged or loose wiring can disrupt the communication between the TPS and the engine, leading to TBW problems.
  • Programming Errors: Errors in the programming of the ECM can also cause TBW issues.

Is It Costly to Repair Throttle By Wire Problems in a Harley?

The cost of repairing TBW problems in a Harley can vary, depending on the specific issue and the parts that need to be replaced. For instance, replacing a faulty TPS can cost between $150 and $250, with the majority of the cost being for the labor charge. In some cases, the repair costs can be significantly higher.

Can I Ride My Harley with a Malfunctioning Throttle By Wire System?

While it’s technically possible to ride a Harley with a malfunctioning TBW system, it’s not advisable. A faulty TBW system can lead to an improper fuel-air ratio, reduced fuel economy, an overheated engine, and faulty catalytic converters, potentially damaging other parts of your bike. Therefore, if you encounter any TBW issues, it’s best to get the problem diagnosed and fixed as soon as possible.

In conclusion, while the Throttle By Wire system in Harley Davidson motorcycles enhances the riding experience, it’s also prone to specific issues. Understanding these problems, their symptoms, and how to fix them can ensure a safer and smoother ride.


How Do You Reset the Throttle By Wire on a Harley?

To reset the throttle by wire on a Harley, turn off the motorcycle, then turn the ignition to the ‘on’ position without starting the engine. Slowly rotate the throttle to the fully open and closed positions several times. Finally, turn the ignition off and then start the engine to complete the reset process.

What Causes Throttle to Stick on Harley?

Throttle sticking on a Harley can be caused by various factors, including a dirty or misaligned throttle body, damaged cables (in non-throttle by wire models), worn-out springs, or issues with the throttle position sensor. Regular maintenance and cleaning can help prevent these issues.

Why Is Drive By Wire Better?

Drive by wire, including throttle by wire systems, offers improved responsiveness, more precise control, and the ability to integrate with advanced electronic systems like traction control and cruise control. It eliminates the need for physical cables, reducing maintenance and providing smoother operation.

What Are the Disadvantages of Ride-By-Wire?

The disadvantages of ride-by-wire include potential electronic failures, which may be more complex and expensive to diagnose and repair compared to mechanical systems. Also, some riders may prefer the tactile feedback of a traditional cable-operated throttle, which ride-by-wire systems lack.