New Holland TMF 151 – TMF (Tractor Multi-Function) Controller: Communications Lost with Transmission Controller

A Controller Area Network (CAN) bus communication failure. The system has detected that the expected data packets from the transmission controller are missing or timing out.

• TG215
• TG275
• T8010
• T8020
• T8030
• T8040
• T8050
• T7000 Series
• TM120-TM175
• TS115A
• TS135A
• Magnum
• Steiger

1. 1

   Verify system voltage: Load-test the battery and ensure voltage does not drop below 10.5V during cranking. Check the alternator output.

2. 2

   Check fuses and relays: Verify the power supply fuses to the Transmission Controller.

3. 3

   Test CAN bus resistance: Turn the ignition switch OFF. Measure the resistance between CAN High and CAN Low at the diagnostic port (should read approximately 60 ohms).

4. 4

   Test CAN bus voltage: Turn the key ON. Measure the voltage of CAN High and CAN Low to ground (CAN High should be slightly above 2.5V, CAN Low slightly below 2.5V).

5. 5

   Inspect grounds: Check the cab grounds, engine block ground strap, and the specific ground wire for the transmission controller for high resistance.

1. 1

   Disconnect Power

   Turn off the tractor and disconnect the negative battery terminal to prevent electrical spikes.

2. 2

   Locate the Modules

   Locate the TMF Controller (typically in the right-hand console/armrest) and the Transmission Controller (location varies by model, often under the cab floor or mounted near the transmission housing).

3. 3

   Inspect Connectors

   Disconnect the wiring harnesses at both the TMF and Transmission controllers. Inspect the pins for corrosion, moisture ingress, or pushed-back pins. Clean with electrical contact cleaner if necessary.

4. 4

   Perform Continuity Testing

   Using a multimeter, check the continuity of the CAN High and CAN Low wires end-to-end between the TMF and the Transmission Controller. Repair any breaks or chafed insulation.

5. 5

   Verify Module Power/Ground

   Reconnect the battery. With the key ON, probe the transmission controller harness connector to ensure it is receiving 12V switched power and has a solid ground.

6. 6

   Clear Codes and Retest

   Reconnect all modules. Turn the key ON and use the diagnostic menu to clear the TMF 151 code.

7. 7

   Module Replacement

   If the wiring, power, and grounds are 100% verified and the code returns immediately, the CAN transceiver inside the Transmission Controller (or rarely, the TMF) has failed. Replace the faulty controller and have a dealer flash/calibrate the new module.