Troubleshooting Bobcat 873 Joystick Switches

[MikePhua]

The Bobcat 873 is a versatile skid steer loader, renowned for its strength, reliability, and agility in a variety of construction, landscaping, and agricultural applications. As with any piece of heavy equipment, proper functionality of all its systems is essential to maintain smooth operation. One common issue that can arise is problems with the joystick switches, which are responsible for controlling key functions such as the loader’s drive, lift, tilt, and auxiliary hydraulics.
In this article, we will discuss the functionality of Bobcat 873 joystick switches, common issues that might arise, and practical steps to troubleshoot and resolve these problems.
Understanding the Bobcat 873 Joystick Switches
The joystick on the Bobcat 873 serves as the main control mechanism for the machine's movement and attachment functions. The machine uses a hydraulic system to drive the wheels, raise or lower the lift arms, and operate auxiliary hydraulic functions (e.g., grapple, auger, or other attachments). The joystick integrates switches that send electrical signals to actuate various functions.
Typically, the joystick has two primary switches:

1. Drive and Lift Control – These controls handle forward, reverse, and the raising/lowering of the loader arms.
   
2. Auxiliary Hydraulics Control – This switch is used for controlling attachments that require hydraulic power beyond what is needed for basic lift and drive functions.
   

Additionally, some models have buttons for additional controls, such as a horn, lights, or a third auxiliary circuit for even more complex attachments.
Common Problems with Joystick Switches
Several issues can affect the functionality of the joystick switches. Some of the most common include:

1. Unresponsive Joystick Controls – The most frequent issue reported is a joystick that fails to activate one or more functions. This can happen if the switch itself is faulty, the wiring is damaged, or there’s an issue with the joystick sensor.
   
2. Erratic or Uncontrolled Movements – Sometimes, users experience erratic movement from the loader arms or drive wheels, even when the joystick is in a neutral position. This could be due to electrical faults, dirty or worn switches, or issues with the hydraulic solenoids.
   
3. Auxiliary Hydraulics Not Responding – In cases where the auxiliary hydraulics aren’t working as expected, it could be due to a malfunction in the joystick's auxiliary control switch or the hydraulic system itself.
   
4. Physical Damage to Joystick or Switches – Exposure to heavy debris, water, or extreme conditions can lead to physical damage to the joystick assembly or switches. Over time, wear and tear on components can cause them to fail.
   

Troubleshooting Joystick Switch Issues
When troubleshooting joystick switch problems on the Bobcat 873, a systematic approach is needed to identify the source of the issue. Below are some practical steps to help you pinpoint and resolve joystick switch issues:

1. Check for Electrical Issues
   • Inspect the wiring harness connected to the joystick. Look for signs of wear, corrosion, or disconnected wires.
     
   • Use a multimeter to check the continuity of the wiring and ensure the switches are receiving power. If the wires are intact but the switches still don’t respond, the issue may lie within the switch itself.
     
2. Test the Joystick Switches
   • Remove the joystick switch cover to gain access to the electrical contacts inside.
     
   • Manually test the switches by actuating them while checking the voltage output. You should see a fluctuation in voltage when the switch is engaged. If there is no change in voltage, the switch is likely defective and may need to be replaced.
     
3. Inspect Hydraulic System
   • If the joystick functions seem to operate intermittently or erratically, there may be issues with the hydraulic control valves or solenoids. Check for proper hydraulic fluid levels and make sure there are no leaks in the system.
     
   • Verify the functionality of the solenoids by testing their electrical signal and operation.
     
4. Examine the Joystick Mechanism
   • Over time, dirt, grime, or hydraulic fluid may build up inside the joystick mechanism, impairing its operation. Disassemble the joystick and clean it thoroughly. Be sure to remove any debris or blockages that could hinder smooth movement.
     
5. Check Calibration and Settings
   • In some cases, the issue may stem from the joystick’s calibration. Ensure that the joystick is calibrated correctly and that the software settings are configured to match the loader’s operating specifications.
     

Replacing Joystick Switches
If troubleshooting reveals that the joystick switches are faulty and need replacing, the process is relatively straightforward, but it requires a methodical approach.

1. Disconnect Power: Always start by disconnecting the battery to avoid any electrical accidents.
   
2. Remove the Joystick: To access the switches, you’ll need to remove the joystick assembly. This may involve unscrewing mounting bolts or removing covers depending on the model.
   
3. Replace the Switches: Once the joystick is disassembled, you can replace the faulty switches. Be sure to install the new switches in the same orientation as the old ones to maintain proper function.
   
4. Reassemble and Test: After replacing the switches, reassemble the joystick, reconnect the electrical wiring, and test the controls to ensure proper operation.
   

Preventative Maintenance for Joystick Switches
To prevent future issues with your Bobcat 873 joystick switches, regular maintenance is key. Some tips include:

1. Keep the Joystick Clean: Ensure that the joystick is kept clean and free of dirt, mud, or other debris that could affect the switches. Regularly inspect and clean the joystick mechanism to prevent buildup.
   
2. Check Hydraulic Fluid Regularly: Low or dirty hydraulic fluid can cause performance issues with the loader arms and auxiliary hydraulics. Ensure that the hydraulic system is filled to the proper level and use high-quality fluid for optimal performance.
   
3. Inspect Wiring and Connectors: Regularly inspect the wiring and electrical connectors for signs of wear or corrosion. Clean and lubricate connectors to maintain a secure electrical connection.
   
4. Follow Manufacturer’s Guidelines: Always refer to the Bobcat 873 operator’s manual for specific instructions on joystick maintenance and troubleshooting. Regular service intervals and recommended parts will help keep your machine running smoothly.
   

Conclusion
The Bobcat 873 is a highly capable and versatile machine, but like all heavy equipment, it is susceptible to issues with its control systems. Joystick switches are critical to the smooth operation of the loader, and problems with them can cause significant downtime. By following the troubleshooting steps outlined in this article, you can identify the root causes of joystick switch issues and restore your machine’s functionality. Regular maintenance will also help prevent problems from occurring, ensuring your Bobcat 873 continues to deliver reliable performance on the job site.