Bobcat T595 Bob-Tach Troubleshooting and Electrical System Reliability

[MikePhua]

The T595 and Its Attachment Interface Evolution
The Bobcat T595 compact track loader was introduced in the late 2010s as part of Bobcat’s M2-Series, designed to deliver high performance in a mid-size footprint. With a rated operating capacity of 2,200 lbs and a turbocharged 74-horsepower engine, the T595 quickly became a favorite among contractors, landscapers, and rental fleets. One of its standout features is the Bob-Tach system—a hydraulic-powered quick coupler that allows operators to change attachments without leaving the cab.
Bobcat Company, founded in 1947 in North Dakota, pioneered the skid steer loader and has remained a leader in compact equipment innovation. The Bob-Tach system evolved from manual levers to hydraulic actuation, and later to electronic control integration. While this advancement improved efficiency, it also introduced new diagnostic challenges when the system fails to respond.
Terminology Clarification

• Bob-Tach: Bobcat’s proprietary quick attachment system, available in manual and hydraulic versions.
  
• Solenoid valve: An electrically actuated valve that controls hydraulic flow to the coupler cylinders.
  
• CAN bus: A communication protocol used in modern machines to link electronic control units.
  
• Interlock system: A safety feature that prevents certain functions unless specific conditions are met.
  

Common Symptoms of Bob-Tach Failure
When the Bob-Tach system malfunctions, operators may encounter:

• No response when pressing the coupler switch
  
• Audible click from solenoids but no hydraulic movement
  
• Coupler pins stuck in locked or unlocked position
  
• Error codes on the display related to attachment control
  
• Hydraulic fluid level normal but no actuation pressure
  

A contractor in Alberta reported that his T595’s Bob-Tach stopped working during a busy grading job. After checking the fuse and switch, he discovered a loose ground wire near the control module. Re-securing the connection restored full function.
Diagnostic Strategy and Electrical Checks
Troubleshooting begins with verifying electrical integrity:

• Check fuse panel for blown fuses related to the Bob-Tach circuit
  
• Test voltage at the coupler switch and solenoid connectors
  
• Inspect wiring harness for abrasion, corrosion, or loose terminals
  
• Use a multimeter to confirm continuity and ground path
  
• Scan the machine for fault codes using a diagnostic tool
  

Recommended tools:

• Digital multimeter with continuity and voltage modes
  
• Electrical contact cleaner and dielectric grease
  
• Bobcat Service Analyzer or compatible CAN bus scanner
  
• Torque wrench for securing connectors and terminals
  

A technician in Georgia used a CAN bus scanner to identify a fault in the attachment control module. After replacing the module and updating firmware, the Bob-Tach resumed normal operation.
Hydraulic System Considerations
If electrical components are functioning, the issue may lie in the hydraulic circuit:

• Inspect coupler cylinders for seal damage or piston binding
  
• Check solenoid valve for contamination or spool sticking
  
• Verify hydraulic pressure at the coupler circuit using a gauge
  
• Replace hydraulic filters and flush the system if debris is found
  
• Ensure the hydraulic fluid is at correct level and viscosity
  

Solutions:

• Clean valve block and test spool movement manually
  
• Replace solenoid coil if resistance is outside spec
  
• Use OEM hydraulic fluid to maintain seal compatibility
  
• Install inline pressure gauge for future diagnostics
  

A fleet manager in Texas added quick-connect test ports to his T595 units, allowing technicians to verify hydraulic pressure without disassembly.
Interlock and Safety System Dependencies
The Bob-Tach system is tied to the loader’s interlock system, which includes:

• Seat sensor to detect operator presence
  
• Park brake status
  
• Loader arm position
  
• Attachment recognition via electrical pins
  

If any of these conditions are unmet, the Bob-Tach may be disabled. Operators should:

• Sit fully in the seat and fasten the seat bar
  
• Engage the park brake before attempting to unlock
  
• Lower the arms to ground level
  
• Ensure attachment is properly seated and connected
  

A crew in British Columbia trained operators to follow a startup checklist that included interlock verification. This reduced Bob-Tach failures and improved attachment change efficiency.
Preventive Maintenance and Long-Term Reliability
To keep the Bob-Tach system reliable:

• Clean coupler pins and cylinders weekly
  
• Inspect wiring harness quarterly for wear
  
• Replace hydraulic filters every 500 hours
  
• Lubricate pivot points and solenoid mounts
  
• Monitor system voltage and battery health
  

Operator tips:

• Avoid forcing the coupler switch repeatedly if unresponsive
  
• Use float mode when aligning attachments
  
• Report any unusual sounds or delays during actuation
  
• Store attachments on level ground to ease connection
  

A technician in Georgia added LED indicators to the coupler switch panel, giving operators visual confirmation of lock status and reducing miscommunication.
Conclusion
The Bobcat T595’s Bob-Tach system is a powerful tool for attachment versatility, but its performance depends on a well-maintained electrical and hydraulic foundation. When issues arise, structured diagnostics and preventive care can restore function quickly and avoid costly downtime. Whether grading, lifting, or trenching, a responsive coupler system keeps the T595 adaptable and efficient. In compact equipment, control precision is just as vital as horsepower.