Troubleshooting the AWS 2-Speed Lockout on the A300 Skid Steer

[MikePhua]

Introduction: The Challenge of the AWS 2-Speed Lockout
The A300 skid steer is a popular machine known for its versatility and power. Among its features, the AWS 2-speed system (Auto Wheel Speed) stands out for offering efficient performance on various terrains, allowing operators to switch between slow, powerful speeds for heavy lifting and faster speeds for travel. However, a common issue faced by some owners is a locked-out 2-speed system, which prevents the machine from shifting between these speeds, severely affecting the machine’s productivity.
This article will explore the causes of a locked-out AWS 2-speed system on the A300, possible solutions, and preventative measures to ensure the machine operates at peak efficiency. Additionally, we’ll delve into how these issues are typically diagnosed and resolved, along with tips from experienced operators.
Understanding the AWS 2-Speed System

1. How the AWS 2-Speed System Works
   The AWS 2-speed system on the A300 is designed to automatically switch between two speeds based on the load and terrain conditions. It allows the machine to:
   • Move at high speeds (approximately 12 mph) for efficient travel.
     
   • Operate at low speeds (around 5 mph) when extra power is needed for lifting or heavy tasks.
     
   The system typically uses a hydraulic motor and sensors to adjust the speed in real-time, helping optimize fuel consumption and performance.
   The key components involved in the AWS 2-speed system include:
   • The transmission unit, which controls the speed settings.
     
   • Speed sensors that detect wheel speed and adjust accordingly.
     
   • The hydraulic system that engages or disengages the 2-speed mode.
     
2. Symptoms of a Locked-out 2-Speed System
   A common symptom of a locked-out 2-speed system is that the A300 will only operate at low speed, with no ability to shift into the higher gear. This results in slower operation, particularly for travel, making the skid steer inefficient for tasks that require quick movement across large areas.
   Other symptoms of a malfunctioning AWS 2-speed system include:
   • A warning light or message on the dashboard, indicating a malfunction.
     
   • Erratic or unresponsive speed changes when trying to switch gears.
     
   • Excessive noise from the transmission or hydraulic system during acceleration.
     
   User Experience Example:
   One user shared their experience with a similar issue in their A300, where the skid steer got "stuck" in low gear after a particularly heavy lifting session. Despite multiple attempts to shift gears, the machine remained locked in low speed, making it a slow and cumbersome process to move around.
   

Causes of the Locked-out AWS 2-Speed System
Several factors could lead to the 2-speed lockout on the A300. Most of these issues stem from either the hydraulic system, sensors, or the transmission unit, all of which work together to control the 2-speed functionality.

1. Hydraulic System Issues
   The hydraulic system is integral to the 2-speed mode. If there is a fluid leak, low fluid levels, or any issue with the hydraulic pressure, the system might not engage the 2-speed properly.
   Potential causes include:
   • Clogged or dirty filters, which restrict hydraulic fluid flow.
     
   • A worn-out hydraulic pump that fails to deliver the proper pressure.
     
   • Damaged hydraulic hoses that cause fluid leaks and prevent proper function.
     
2. Faulty Speed Sensors
   Speed sensors are responsible for detecting the wheel speed and automatically switching between slow and fast modes. If the sensors malfunction or become dirty, they can cause the system to lock into one speed or fail to detect the correct speed change.
   
3. Transmission Problems
   The transmission system is designed to switch between the gears based on the input from the sensors and the hydraulic system. If there is an issue within the transmission unit, such as a stuck valve or broken gear, it may prevent the system from shifting gears effectively.
   Wear and tear in the transmission components over time can also contribute to a failure in shifting, particularly if the machine has been used extensively for heavy work without proper maintenance.
   
4. Electrical Problems
   An electrical malfunction can also prevent the 2-speed system from engaging or disengaging correctly. Wiring issues, poor connections, or a faulty relay can disrupt the communication between the components of the system.
   Real-Life Case Study:
   A user reported that their A300 skid steer wouldn’t shift into the higher gear, despite trying all troubleshooting methods. Upon inspection, they discovered that a corroded connection in the wiring of the speed sensor was preventing the system from properly receiving input, locking it into low speed.
   

How to Fix the Locked-out AWS 2-Speed System

1. Check and Maintain the Hydraulic System
   First and foremost, ensure that the hydraulic fluid is at the correct level and free of contaminants. Regularly inspect the hydraulic filter for dirt or debris, which could cause blockages. If needed, replace the filters and ensure that the hydraulic lines are intact with no leaks. If the hydraulic pump shows signs of wear, it may need to be replaced.
   Routine Maintenance:
   • Check hydraulic fluid levels monthly or after every major use.
     
   • Replace filters annually or as recommended by the manufacturer.
     
   • Inspect the hydraulic hoses for cracks, leaks, or wear.
     
2. Inspect and Clean the Speed Sensors
   Clean the speed sensors and inspect them for any visible signs of damage or malfunction. It may also be beneficial to test the sensors using diagnostic tools to ensure they are sending the correct signals to the transmission.
   
3. Examine the Transmission Unit
   If the hydraulic and sensor systems are functioning properly, the next step is to inspect the transmission unit. This may involve checking for fluid leaks, examining the internal parts for wear, and testing the functionality of the gear shift mechanism. If necessary, take the machine to a certified technician for a more in-depth inspection of the transmission.
   
4. Electrical System Check
   Ensure all electrical connections are tight and free from corrosion. If you encounter electrical issues, it’s recommended to use a multimeter to test the wiring and relay systems. Replace any damaged wiring or connectors to restore full functionality.
   

Preventative Measures for Future Issues

1. Regular Maintenance Checks
   Prevent future lockout issues by performing regular maintenance on your A300 skid steer, including inspecting the hydraulic system, speed sensors, transmission, and electrical components. Establishing a proactive maintenance schedule can help avoid issues before they develop into serious problems.
   
2. Follow Manufacturer Recommendations
   Adhere to the maintenance guidelines provided by the manufacturer for fluid changes, sensor inspections, and mechanical checks. Regular servicing will extend the lifespan of the AWS 2-speed system and ensure it operates as intended.
   

Conclusion: Ensuring Optimal Performance of the AWS 2-Speed System
A locked-out AWS 2-speed system on the A300 skid steer can be frustrating, but with proper diagnostic steps and maintenance, the issue can often be resolved. Whether the cause lies in the hydraulic system, speed sensors, transmission, or electrical components, addressing the problem early will ensure your A300 continues to perform optimally.
Regular inspection and maintenance are key to preventing issues with the AWS 2-speed system. By understanding the root causes and symptoms of this malfunction, operators can take the necessary steps to restore functionality and keep their machine running smoothly for years to come.