SHIELD AS 9Y4561 - Caterpillar

Hydraulic oil temperature must be between 40° C (104° F) and 60° C (140° F) when running IMV cracking calibrations.If the IMV PHMV solenoid calibrations are suspected to be the root cause of a controllability issue, use the following procedure:Note: Prior to performing any calibration procedures, run a system status report through Cat ET.
Perform all on machine calibrations for the ACS main valve. Perform the calibration procedures for the center manifold stems as well as all IMV cracking calibrations.
Compare original calibration values to new calibration values. If the IMV cracking calibration has changed by more than 15mA from the original cracking calibration, something has likely malfunctioned on that particular IMV.
If the IMV consistently fails calibration or the calibration has changed by 15 mA in 2 above, inspect the IMV valve and replace the PHMV. The calibration slope must be entered into machine software using Cat ET. Refer to Testing and Adjusting, UENR6243, "Main Control Valve - Calibrate".
After all on machine calibrations are complete re-evaluate the controllability issue. If the issue still exists continue to next step.
For the IMV valves in question, verify the slope entered in Cat ET matches the slope stamped on the solenoid nut. If an IMV solenoid is replaced, the slope must be updated in Cat ET. Note: Unpainted PHMVs have likely been replaced. The slopes of unpainted PHMVs should be checked to verify that the slopes in the software match the slope stamped on the nut. There is the possibility the PHMV was replaced without entering the slope in software.Note: Procedures for running on-machine calibrations and entering PHMV slope calibration data can be found in Testing and Adjusting, UENR6243.