Case IH 31 – Transmission Controller / ECM: REVERSE (SHUTTLE) SYNCHRONIZER SOLENOID COIL SHORT CIRCUIT

The system logs this code when the Reverse (Shuttle) Synchronizer Solenoid experiences a short circuit while the tractor is driven in reverse or in neutral. When this code is active, the Transmission Status Lamps (the Hi/Rabbit and Lo/Turtle lamps) will flash in an alternating manner.

• MX Maxxum
• JXC
• TN Series
• MXU series

1. 1

   Inspect the wiring harness for a short circuit between ECM connector 1, pin 17 and ECM connector 1, pin 3, or a short directly across the two solenoid coil terminals.

2. 2

   Test the Reverse (Shuttle) Synchronizer Solenoid Coil for internal shorts using a multimeter.

3. 3

   Use the tractor's onboard H-Menu diagnostic system (navigate to H9, channel 13) to monitor the switch/sensor functions and verify the solenoid current.

4. 4

   Verify ECM functionality if the wiring and solenoid coil both test within normal parameters.

1. 1

   Disconnect the battery before performing any electrical or transmission service.

   Safety First

2. 2

   Locate the Reverse (Shuttle) Synchronizer Solenoid on the transmission valve block.

   Access the Solenoid

3. 3

   If the diagnostic checks revealed a short in the harness between ECM Connector 1 (Pins 17 and 3) and the solenoid, repair or replace the damaged wiring section.

   Inspect and Repair Wiring

4. 4

   If the solenoid coil is internally shorted, disconnect the electrical connector, unthread/remove the faulty solenoid from the transmission housing, and install the replacement solenoid.

   Replace the Solenoid

5. 5

   Reconnect the solenoid electrical connector and the tractor's battery.

   Reassemble and Reconnect

6. 6

   Clear the fault codes and perform a transmission calibration (auto-calibration of the synchros and clutches) using the H-Menu or an Electronic Service Tool so the ECM can learn the new solenoid's fill times and engagement profile.

   Calibrate the Transmission