Case IH 1557-12 - VCM – VCM: Steering valve controller internal fault

The electrohydraulic steering valve controller has failed its internal RAM (Random Access Memory) test. Because the memory is corrupted or the internal hardware has failed, the controller can no longer safely operate the auto-guidance steering system.

• MAGNUM AFS Connect
• Steiger
• Quadtrac
• Magnum
• Puma
• Optum
• Axial-Flow Combines

1. 1

   Power Cycle: Turn the machine off, wait for the modules to power down completely, and turn the key back on. If the code was caused by a temporary voltage spike corrupting the RAM, a reboot might clear it.

2. 2

   Check Power and Ground: Inspect the wiring harness at the steering valve. Ensure the PVED-CLS controller is receiving stable voltage and has a clean ground. Poor power supply can sometimes trigger false internal module faults.

3. 3

   Bleed the System: Ensure there is no air in the hydraulic steering system, which can cause erratic behavior. Turn the steering wheel fully left and fully right a minimum of 10 times.

1. 1

   Depressurize

   Park the machine on a flat surface, turn off the engine, and relieve hydraulic pressure (pump the brakes and turn the steering wheel until there is no resistance).

2. 2

   Locate the Valve

   Locate the electrohydraulic steering valve block (typically mounted under the cab or near the front axle articulation point, depending on the tractor model).

3. 3

   Disconnect

   Unplug the electrical harness connector from the PVED-CLS module.

4. 4

   Remove the Module

   Remove the mounting screws securing the PVED-CLS controller to the mechanical steering valve body.

5. 5

   Replace Seals

   Remove the old port seals (O-rings) between the module and the valve body. Clean the mating surface and install a new port seal kit.

6. 6

   Install New Module

   Mount the new PVED-CLS module using the provided mounting screws and torque to OEM specifications. Reconnect the electrical harness.

7. 7

   Bleed and Calibrate

   Start the tractor and bleed the steering system (lock-to-lock 10 times). Finally, use the AFS Pro display or the dealer service tool to perform the Auto-Steering Valve Calibration routine.