Case IH 2392 (517966.04) - DEC – Transmission Control Unit (TCU): Clutch A solenoid valve has a short circuit to ground

The transmission controller is detecting that the voltage intended to actuate the Clutch A PWM (Pulse Width Modulation) solenoid is finding a direct path to ground before or at the solenoid. This prevents the solenoid from properly regulating hydraulic pressure to Clutch A, which will result in harsh shifting, failure to engage specific gears, or the transmission defaulting to a protective neutral/limp mode.

• VESTRUM CVX
• Puma 160
• Puma 165
• Puma 170
• Puma 185
• Puma 200
• Puma 215
• Puma 230
• Maxxum 110
• Maxxum 115
• Maxxum 120
• Maxxum 125
• Maxxum 130
• Maxxum 140
• Farmall 95U
• Farmall 105U
• Farmall 115U Pro EP
• Magnum 210
• Magnum 225
• Magnum 275
• MXM Series

1. 1

   Check for accompanying codes: If multiple solenoid codes are present, the issue is likely a shared ground or main harness rub-through rather than a single failed solenoid.

2. 2

   Inspect the wiring harness running from the Transmission Control Unit to the transmission control valve block for pinched wires, melted insulation, or areas where the harness may have rubbed against the chassis, causing a short to ground.

3. 3

   Perform a solenoid resistance test: Disconnect the electrical connector at the Clutch A solenoid and measure the resistance between terminal 1 and terminal 2. It should be between 8 and 11 Ohms. A reading near 0 Ohms indicates the solenoid is internally shorted.

4. 4

   Perform a harness continuity test: With the solenoid disconnected, test the harness-side connector for continuity to ground on the power supply wire. If continuity to ground is found, repair or replace the wire harness.

5. 5

   Perform a transmission hydraulic pressure test: If no electrical fault is found, rule out mechanical faults or a stuck valve.

1. 1

   Prepare the tractor for repair

   Park the tractor on a level surface, engage the parking brake, turn off the engine, and disconnect the battery.

2. 2

   Locate the transmission control valve assembly

   Locate the transmission control valve assembly (typically mounted on the side or top of the transmission housing).

3. 3

   Clean the transmission control valve block

   Thoroughly clean the exterior of the transmission control valve block to prevent dirt or debris from entering the hydraulic system during disassembly.

4. 4

   Disconnect the electrical connector

   Disconnect the electrical connector from the Clutch A PWM solenoid valve.

5. 5

   Remove the retaining bolt(s)

   Remove the retaining bolt(s) securing the Clutch A solenoid valve to the valve block.

6. 6

   Remove the solenoid valve assembly

   Carefully pull the solenoid valve assembly out of the transmission control valve block.

7. 7

   Inspect the valve bore

   Inspect the valve bore for any debris or scoring. If debris is found, the valve block may need to be flushed.

8. 8

   Prepare the new solenoid valve

   Ensure the O-rings on the new solenoid valve are in good condition. Coat the new valve components and O-rings with clean transmission oil (CASE IH AKCELA NEXPLORE™ FLUID) prior to installation.

9. 9

   Install the new solenoid valve

   Insert the new Clutch A solenoid valve into the valve block.

10. 10

    Secure the solenoid valve

    Install the retaining bolt(s) and tighten them to a torque value of 27 Nm.

11. 11

    Reconnect the electrical connector

    Reconnect the electrical connector to the solenoid.

12. 12

    Restore power and clear codes

    Reconnect the battery and start the tractor. Clear the stored fault codes.

13. 13

    Perform a transmission clutch calibration

    Perform a transmission clutch calibration (Quick Fill calibration) using the instrument cluster (H-Menu) or a diagnostic tool to ensure the TCU learns the engagement characteristics of the new Clutch A solenoid.