New Holland TRANS 135 – Transmission Controller (TRANS) / Tractor Multi-Function / Hitch Controller (TMF): Communication lost with the armrest controller

The machine's Controller Area Network (CAN) data bus has lost the signal between the transmission/hitch modules and the Armrest Controller (ARU).

• TG210
• TG230
• TG255
• TG285
• TG305
• T8010
• T8020
• T8030
• T8040
• T9050
• Magnum
• STX Steiger

1. 1

   Verify if the armrest controller has power and ground (a completely dead controller usually points to a power failure or dead module)

2. 2

   Inspect connector C137 at the armrest controller to ensure it is correctly installed, fully seated, and free of damage

3. 3

   Check for moisture ingress or aging connectors in the housing and pins, especially in humid climates

4. 4

   Test the Tractor Data Bus (TDB) CAN bus wiring harness for continuity, shorts to ground, or open circuits between the transmission controller and the armrest controller

1. 1

   Disconnect battery

   Disconnect battery power before servicing the electrical system.

2. 2

   Disconnect connector

   Access the Armrest Controller (ARU) and disconnect connector C137.

3. 3

   Clean and dry pins

   Clean the connector pins with contact cleaner and dry them completely if moisture or corrosion is found. Reconnect and test the machine.

4. 4

   Verify power and ground

   If the code persists, use a multimeter to verify 12V power and solid ground at the ARU harness.

5. 5

   Replace controller

   If power, ground, and CAN bus continuity are all within specification, the Armrest Controller itself has failed internally and must be replaced.

6. 6

   Program and calibrate

   Hook up the New Holland Electronic Service Tool (EST) to capture the controller, download the machine-specific software/configuration, and calibrate it.