Case IH 517959-01 - DEC – DEC: Transmission A2 clutch solenoid electrical circuit fault - Voltage below normal

This code indicates that the electrical circuit controlling the A2 clutch solenoid in the transmission is experiencing a low voltage condition. This prevents the solenoid from properly building or releasing the hydraulic pressure required to engage or disengage the A2 transmission clutch.

• MAGNUM AFS Connect

1. 1

   Check the battery voltage and charging system for a system voltage drop (often below 11.5 volts) during operation, extended cranking, or due to a failing alternator regulator.

2. 2

   Inspect the wiring harness between the DEC (Drivetrain Electronic Controller) and the A2 clutch solenoid for open circuits, wires shorted to ground, or chafing.

3. 3

   Disconnect the harness at the transmission controller and the solenoid to inspect the connector ends for damaged, bent, corroded, or dislocated pins.

4. 4

   Verify that the reference voltage supply circuit from the controller to the transmission solenoids is intact and not shorting out.

1. 1

   Safety First

   Park the tractor on a level surface, engage the parking brake, and place the transmission in neutral. Disconnect the battery to prevent electrical shorts during repair.

2. 2

   Harness Repair

   If the diagnostic checks reveal a short to ground or an open wire in the A2 clutch circuit, repair or replace the damaged section of the wiring harness. Clean any corroded connector pins.

3. 3

   Solenoid Replacement

   If the wiring and voltage supply from the DEC are verified to be good, the A2 clutch solenoid itself has likely failed internally and must be replaced. Remove the faulty solenoid valve from the transmission valve block and install the new OEM replacement.

4. 4

   Clear Fault Codes

   Reconnect the battery. You will likely need to use the Case IH Electronic Service Tool (EST) laptop software to clear the inactive fault codes from the DEC memory, as modern software versions often do not allow clearing these specific codes directly from the cab display keypad.

5. 5

   Transmission Calibration

   After replacing a transmission clutch solenoid, a transmission clutch calibration must be performed. Ensure the transmission is in neutral, the parking brake is engaged, engine RPM is set between 800 and 1200, and the transmission sump fluid is at operating temperature (around 75°C - 80°C) before running the calibration.