New Holland 3875 – Engine ECU: Timeout of CAN message TSC1-DR passive

This is a Controller Area Network (CAN) communication error indicating that the Engine Control Unit is not receiving the expected torque and speed command messages (TSC1-DR) from the Driveline/Transmission controller over the CAN bus network.

• T6
• T7
• T8
• T6000
• T7000

1. 1

   Check for accompanying CAN bus timeout codes (e.g., 3332, 3333, or SPN 639) which would indicate a total CAN bus failure rather than an isolated module issue.

2. 2

   Test CAN bus resistance at the diagnostic port with the tractor turned off and battery disconnected. A healthy bus reads ~60 Ohms. 120 Ohms indicates a missing/broken terminating resistor; infinite resistance indicates an open circuit.

3. 3

   Visually inspect the wiring harness between the Engine ECU and the Transmission Controller for chafed wires, stretched harnesses (especially near the armrest or cab pivot points), and loose or corroded connector pins.

4. 4

   Verify the Transmission Controller is receiving proper power and ground; if the module is offline, it cannot broadcast the TSC1-DR message.

1. 1

   Disconnect power

   Turn off the machine and disconnect the battery to prevent electrical shorts during repair.

2. 2

   Locate the break or short

   Based on the multimeter resistance tests, trace the CAN bus lines (CAN_H and CAN_L) from the Engine ECU to the Transmission Controller.

3. 3

   Repair wiring

   If a broken wire is found (commonly near harness flex points), repair the wire using proper solder/crimp techniques and seal it with adhesive-lined heat-shrink tubing.

4. 4

   Service connectors

   Disconnect the plugs at the Engine ECU and Transmission Controller. Spray with electrical contact cleaner. If any pins are pushed back or corroded, extract and replace the pins.

5. 5

   Replace terminating resistors

   If the CAN bus resistance was 120 Ohms, locate the faulty CAN bus terminating resistor (often located behind the cab back cover or in the engine bay) and replace it.

6. 6

   Reassemble and clear codes

   Reconnect all modules and the battery. Use the New Holland E.A.S.Y. diagnostic tool (or equivalent) to clear the inactive fault codes.

7. 7

   Test drive

   Operate the tractor under load to verify that the Engine ECU and Transmission Controller are communicating and the code does not return.