- The control lever is not calibrated properly.
- The pump controls in the pump are suspect.
- The steering pedal position sensors are not calibrated properly.
- The hystat pump controls have excessive leakage.
- The speed sensors are not operating properly.
- Contamination is causing a problem.
The Control Lever Is Not Calibrated Properly
Be sure that the control lever position sensor is calibrated properly. Refer to Testing and Adjusting, "Hystat Operator Control Calibrations" for your machine.
The Pump Controls In The Pump Are Suspect
Refer to Troubleshooting, "Diagnostic Code Procedures" in this manual for troubleshooting procedures.
Ensure that there is not a problem in the electrical components of the steering system that may be causing the hystat pump to operate improperly. Check the monitoring system for any fault codes that are related to Steering Position Sensor 1, Steering Position Sensor 2, Steering Position Sensor 3, the solenoid for the Left Steer, or the solenoid for the Right Steer. If the signals from the steering position sensors are incorrect, the ECM may not be commanding the solenoid to energize properly, and/or the ECM may not be commanding the solenoid to de-energize properly. Correct any problems that are found with any of these components. Once the components are operating correctly then retest the machine for another symptom(s).
If no fault codes exist for the control solenoids for the hystat pump, then the control solenoids for the steering and/or the steering position sensors may require calibration. Refer to Testing and Adjusting, "Calibration" for your machine.
The Steering Pedal Position Sensors Are Not Calibrated Properly
Be sure that the steering pedal position sensors are calibrated properly. Refer to Testing and Adjusting, "Hystat Operator Control Calibrations" for your machine.
The Hystat Pump Controls Have Excessive Leakage
Refer to Testing and Adjusting, "Calibration" for your machine.
The Speed Sensors Are Not Operating Properly
Check the status of the speed sensors in ET. Refer to Testing and Adjusting, "Speed Sensor - Adjust" for your machine. Replace the sensors, if necessary.
Contamination Is Causing A Problem
Inspect the solenoid, swash plate, springs, and edge filters for debris. If debris is found then clean the component and see if that solves the problem. Replace the components, if necessary.