Case IH 56026 – Transmission Controller (TRANS): 2F Valve Coil Circuit is Shorted to 12 Volts When Valve is On.

The 2F clutch solenoid coil is turned on, and the voltage on the low side of the coil is higher than expected. This indicates a short to power (12V).

• STX Steiger
• Case IH Puma series
• Case IH Steiger series
• Case IH CS 150

1. 1

   Check Coil Resistance: Measure the resistance of the 2F clutch solenoid coil. Resistance is temperature-sensitive (e.g., 9.4-11.4 ohms at 40°F, up to 11.7-14.3 ohms at 140°F). Lower resistance indicates an internal short.

2. 2

   Check for Wiring Short to Power: Disconnect the transmission controller connector, turn key ON, turn on all front frame items, and check voltage at the connector cavity. There should be NO voltage.

1. 1

   Replace the Solenoid Coil

   If the resistance test fails (lower than specified), replace the 2F clutch solenoid coil.

2. 2

   Repair the Wiring Harness

   If voltage was found during the wiring check, trace the harness to locate the source of the short to power and repair the damaged wiring. (Note: Dealer mechanics note that hydraulic pipes rubbing against the harness are a common cause of shorts in these circuits).

3. 3

   Test the System

   If no problems were found with the coil or wiring, clear the fault codes. Turn the key switch off and then back on. Start and drive the tractor in forward gears (e.g., 4, 11, 12, 16LO, and 16HI).

4. 4

   Replace the Transmission Controller

   If fault code TRANS 56026 is recorded again after clearing it and test-driving, and steps 1-3 show no faults, replace the transmission controller.