Case IH 2393 (517967.04) - DEC – Transmission Control Unit (TCU) / Transmission ECU: Clutch B solenoid valve - short circuit to ground

The control module has detected a short circuit to ground in the electrical circuit for the Clutch B solenoid valve. The electrical current intended to power the solenoid is finding an unintended path directly to the chassis ground, preventing the solenoid from energizing properly and Clutch B from engaging.

• VESTRUM CVX
• Puma 165
• Puma 180
• Puma 195
• Puma 210
• Puma 225 CVX
• Maxxum MXM 120
• Maxxum MXM 130
• Maxxum MXM 140
• Maxxum MXM 155
• Maxxum MXM 175
• Maxxum MXM 190
• Farmall 95U Pro EP
• Farmall 105U Pro EP
• Farmall 115U Pro EP
• Magnum Series

1. 1

   Access the transmission control valve block by removing the cab floor access panel to reach the Clutch B solenoid.

2. 2

   Test the Clutch B solenoid resistance by disconnecting its electrical connector and measuring across the pins with a multimeter (should be approximately 10 Ohms). If it reads significantly lower or shows continuity to the casing, the solenoid is internally shorted.

3. 3

   Test the wiring harness for a short to ground. With the solenoid disconnected, test the specific signal wire (e.g., pin 2) on the transmission control harness for continuity to the chassis ground.

4. 4

   Inspect the transmission control harness, the main transmission harness, and the TCU connectors for moisture, corrosion, or damaged pins.

1. 1

   Power Down

   Turn off the tractor, remove the key, and disconnect the battery to prevent electrical spikes.

2. 2

   Gain Access

   Remove the cab floor mat and the transmission access cover to expose the transmission valve block.

3. 3

   Repair the Harness (If Applicable)

   If diagnostics revealed a short to ground in the harness, trace the wire back toward the TCU. Locate the chafed insulation, repair the wire using a weatherproof splice, and wrap it in protective loom.

4. 4

   Replace the Solenoid (If Applicable)

   If the solenoid failed the resistance test, disconnect its electrical connector. Remove the retaining fastener holding the Clutch B solenoid valve to the transmission valve block. Pull the old solenoid out, lubricate the O-rings on the new solenoid with clean transmission fluid, and install it into the block. Secure the fastener.

5. 5

   Reassemble

   Reconnect the electrical connector to the solenoid. Reinstall the cab floor access panel and floor mat.

6. 6

   Calibrate

   Reconnect the battery. Turn the key on, clear the stored fault codes from the TCU, and perform a Transmission Clutch Calibration procedure to ensure the TCU learns the fill times and pressures for the new Clutch B solenoid.