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The Bobcat ACS System and Its Evolution
Bobcat’s Advanced Control System (ACS) was introduced in the early 2000s to improve operator precision and safety in skid steer loaders. By integrating electronic sensors, actuators, and control modules, ACS replaced traditional mechanical linkages with programmable logic. This allowed for smoother joystick response, automatic lockouts, and compatibility with multiple control styles. The system became standard in models like the 753, S130, S150, and T250, contributing to Bobcat’s dominance in the compact loader market. By 2010, Bobcat had sold over 500,000 ACS-equipped machines globally.
Understanding the 32-65 Error Code
One of the most common ACS faults is the 32-65 error, which indicates sensor supply voltage out of range. This typically means the 5V reference signal from the controller is interrupted or corrupted. The ACS controller sends this voltage to hand controls, foot pedals, and actuators. If the return signal deviates from expected parameters, the system locks out hydraulic functions to prevent unsafe operation.
Terminology Notes
In Utah, a technician found that a Bobcat 753 locked out hydraulics after sitting in the rain. Cleaning the controller plugs and reseating the harness resolved the issue. In Spain, a mechanic replaced the ACS controller on an S130 and received a 32-23 error. After manually calibrating the unit on the machine, full functionality returned—without dealer intervention.
In Canada, a T250 owner experienced intermittent boom failure. The error code 32-04 pointed to a faulty controller. After replacing the control box and having it programmed by a dealer, all hydraulic functions stabilized. The mechanic noted that these failures were common enough that they kept spare controllers in stock.
Recommended Solutions and Maintenance Tips
ACS errors in Bobcat loaders are often electrical in nature, stemming from corroded connectors, damaged wiring, or failed actuators. The 32-65 code specifically points to voltage irregularities in the sensor supply circuit. While some issues can be resolved with cleaning and inspection, others require controller replacement and calibration. With proper diagnostics and preventive maintenance, operators can restore full hydraulic function and avoid costly downtime. The ACS system, though complex, remains a cornerstone of Bobcat’s control innovation.
Bobcat’s Advanced Control System (ACS) was introduced in the early 2000s to improve operator precision and safety in skid steer loaders. By integrating electronic sensors, actuators, and control modules, ACS replaced traditional mechanical linkages with programmable logic. This allowed for smoother joystick response, automatic lockouts, and compatibility with multiple control styles. The system became standard in models like the 753, S130, S150, and T250, contributing to Bobcat’s dominance in the compact loader market. By 2010, Bobcat had sold over 500,000 ACS-equipped machines globally.
Understanding the 32-65 Error Code
One of the most common ACS faults is the 32-65 error, which indicates sensor supply voltage out of range. This typically means the 5V reference signal from the controller is interrupted or corrupted. The ACS controller sends this voltage to hand controls, foot pedals, and actuators. If the return signal deviates from expected parameters, the system locks out hydraulic functions to prevent unsafe operation.
Terminology Notes
- ACS Controller: The central module that manages input from sensors and sends commands to hydraulic actuators.
- Actuator: A servo motor that moves the hydraulic spool based on electronic signals.
- Sensor Supply Voltage: A regulated 5V signal used to power position sensors in the control handles and pedals.
- Spool Lock: A safety feature that prevents unintended hydraulic movement when errors are detected.
- Corroded Connectors: Moisture intrusion, especially after rain or washing, can oxidize pins in the controller plug. Cleaning with contact cleaner and applying dielectric grease often restores function.
- Broken or Rubbed Wires: The ACS harness runs through tight spaces near the seat and engine compartment. Vibration and friction can wear insulation, causing shorts or open circuits.
- Faulty Actuators: Older actuators may fail mechanically or electronically. Newer replacements require software calibration with version 63 or higher, which only dealers can perform.
- Uncalibrated Controllers: Replacing the ACS controller without calibration results in a 32-23 error. Some units arrive pre-programmed, allowing field calibration without a laptop, but this varies by model and firmware.
In Utah, a technician found that a Bobcat 753 locked out hydraulics after sitting in the rain. Cleaning the controller plugs and reseating the harness resolved the issue. In Spain, a mechanic replaced the ACS controller on an S130 and received a 32-23 error. After manually calibrating the unit on the machine, full functionality returned—without dealer intervention.
In Canada, a T250 owner experienced intermittent boom failure. The error code 32-04 pointed to a faulty controller. After replacing the control box and having it programmed by a dealer, all hydraulic functions stabilized. The mechanic noted that these failures were common enough that they kept spare controllers in stock.
Recommended Solutions and Maintenance Tips
- Inspect and Clean Electrical Connectors Quarterly: Use dielectric grease to prevent corrosion.
- Check Harness Routing: Look for pinch points or areas where wires rub against metal.
- Replace Actuators with Dealer Support: Calibration is required for compatibility with newer firmware.
- Invest in an Electrical Manual: It contains troubleshooting charts not found in the standard service manual.
- Monitor for Gurgling Sounds Near Actuators: This may indicate internal servo failure or fluid bypass.
ACS errors in Bobcat loaders are often electrical in nature, stemming from corroded connectors, damaged wiring, or failed actuators. The 32-65 code specifically points to voltage irregularities in the sensor supply circuit. While some issues can be resolved with cleaning and inspection, others require controller replacement and calibration. With proper diagnostics and preventive maintenance, operators can restore full hydraulic function and avoid costly downtime. The ACS system, though complex, remains a cornerstone of Bobcat’s control innovation.
