Case IH 2576 – Transmission Control Unit (TCU) / Transmission Controller: The 4F Clutch Lube Solenoid Driver has detected an open or short circuit condition

The transmission controller has measured the current draw from the 4F clutch lube solenoid circuit and found it to be outside the expected limit. This means the circuit is either open (broken wire/failed coil) or shorted to ground/power.

• Steiger T4B
• Steiger
• Quadtrac
• STX 350
• STX 400
• STX 450
• STX 500
• STX 550
• STX 600
• 9380
• 9390

1. 1

   Visually inspect the wiring harness between the transmission controller and the 4F clutch lube solenoid for abnormal routing, chafing, or wire damage.

2. 2

   Ensure the connectors at both the transmission controller and the solenoid are tight, undamaged, and free of corrosion or pushed pins.

3. 3

   Disconnect the harness from the transmission controller and the solenoid. Use a multimeter to check for continuity from end to end, and check for a short to ground or a short to power in the wiring.

4. 4

   Measure the resistance across the pins of the 4F clutch lube solenoid coil. If resistance is out of specification, the coil has failed (if the problem is temperature-sensitive, the coil is likely beginning to fail internally).

5. 5

   If the wiring harness and the solenoid coil both test perfectly, check the transmission controller itself as it may have failed.

1. 1

   Power Down

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

2. 2

   Access the Solenoid

   Locate the 4F clutch lube solenoid on the transmission control valve body.

3. 3

   Remove the Faulty Component

   If diagnostics point to the solenoid, disconnect its electrical connector. Remove the retaining bolts or snap ring holding the solenoid in place and pull the solenoid cartridge from the valve body.

4. 4

   Install the New Solenoid

   Lubricate the O-rings on the new solenoid with clean transmission fluid. Carefully insert it into the valve body and secure it with the retaining hardware.

5. 5

   Repair Wiring (If Applicable)

   If the harness was the culprit, repair the broken/shorted wire using weather-sealed butt connectors or replace the affected harness section.

6. 6

   Reassemble and Clear Codes

   Reconnect the electrical connector to the solenoid and reconnect the battery. Use the Electronic Service Tool (EST) or the in-cab display to clear the inactive fault code.

7. 7

   Test Operation

   Start the tractor and shift through the forward and reverse gears to ensure the 4F clutch modulates correctly and the fault code does not return.