Case IH 56092 – Transmission Controller (TRANS): Diff Lock Relay Coil circuit is shorted to 12 volts when commanded ON.

The transmission controller provides the ground path for the differential lock relay coils (relays #6 and #7). When commanded ON, the ground path is activated, but the voltage on the low side of the coil is reading higher than expected.

• STX Steiger
• STX Series
• Steiger
• Quadtrac
• Magnum
• Puma

1. 1

   Replicate the fault by clearing the TRANS 56092 code, turning the key switch OFF then ON, and turning the differential locks ON.

2. 2

   Perform a heat cycle test by monitoring transmission faults for several minutes, as relay coils often fail as they heat up.

3. 3

   Remove relays #6 and #7 and check voltage at cavity 2 of each relay seat. There should be no voltage present on the ground circuit. If voltage is found, the wiring harness is shorted to power.

4. 4

   Visually inspect the relay seat for wire damage, bent pins, or loose terminals.

1. 1

   Clear fault code

   Clear fault code TRANS 56092 from the transmission controller.

2. 2

   Replace differential lock relays

   Replace the differential lock relays (relays #6 and #7) with new OEM relays. Turn the key switch ON and engage the differential locks. If the code does not return, the repair is complete.

3. 3

   Repair wiring harness

   If the code persists after relay replacement, trace the wiring harness between the relay block and the transmission controller. Locate the source of the 12V short and repair the damaged wire.

4. 4

   Replace transmission controller

   If the relays are new, the relay seat is in good condition, and the wiring harness tests perfectly with no shorts to power, the transmission controller itself has failed and will need to be replaced and recalibrated.