Case IH 2724 (517966.03) - DEC – Transmission Control Unit (TCU): Clutch A solenoid- LSD short to high voltage

The controller has detected that the circuit for the Clutch A solenoid is experiencing a 'short to high voltage'. This means the voltage on the solenoid's control line exceeds the expected operating parameters, typically caused by the signal wire shorting directly to a power source.

• VESTRUM CVX
• Puma 125
• Puma 165
• Puma 180
• Puma 195
• Puma 210
• Puma 225 CVX
• Farmall 85C
• Farmall 95C
• Farmall 105C
• Farmall 95U Pro EP
• Farmall 105U Pro EP
• Farmall 115U Pro EP
• Maxxum 120
• Maxxum 130
• Maxxum 140
• Maxxum 155
• Maxxum 175
• Maxxum 190
• Magnum MX210
• Magnum MX230
• Magnum MX255
• Magnum MX285
• Magnum 7100 series
• Magnum 7200 series
• Magnum 8900 series

1. 1

   Turn off the engine and ensure that all pressure is relieved from the hydraulic circuits before removing any caps, covers, or valves.

2. 2

   With the cab floor removed (or accessing the transmission valve block directly), disconnect the electrical connector (e.g., connector C161 or X-100) to the Clutch A solenoid.

3. 3

   Use a suitable multi-meter to check the solenoid itself for an internal open or short circuit.

4. 4

   Disconnect the processor/controller connectors and test the wiring harness for a short to ground or a short to a high voltage source.

5. 5

   If electrically sound, energize the solenoid (using a diagnostic tool or by holding the downshift button while the clutch pedal is depressed) and observe the pressure reading on a gauge. It should typically read 16–18 bar or 20–22 bar.

1. 1

   Preparation

   Safely park the machine, clean and dry the working area to prevent contamination, and relieve all hydraulic pressure.

2. 2

   Access the Valve Block

   Locate the transmission external controls where the Clutch A solenoid valve is mounted.

3. 3

   Wiring Repair

   If the diagnostic checks revealed a short to high voltage in the harness (e.g., melted insulation or chafed wires touching a power line), repair or replace the affected wiring harness section.

4. 4

   Solenoid Replacement

   If the solenoid itself is internally shorted, disconnect its electrical connector, remove the retaining bolt, and extract the Clutch A solenoid valve.

5. 5

   Installation

   Install the new solenoid valve, ensuring the O-rings are properly seated and lubricated. Reconnect the electrical connector.

6. 6

   Clear Codes

   Supply power to the controller and use the diagnostic menu (e.g., the 'HC' menu) to erase all stored error codes.

7. 7

   Calibration

   Perform a transmission clutch calibration. Access the diagnostic menu (often Channel 4 or 5 for Clutch A quick fill adjustment) to calibrate the applied and released positions of the new solenoid to ensure smooth clutch engagement.