New Holland ENG 3327 – Engine ECU: Timeout of CAN Message TCO1 (Tachograph)

The Engine Control Unit (ECU) has stopped receiving the expected "TCO1" CAN bus message from the Tachograph control unit within the required timeframe. The TCO1 message typically broadcasts driver identification and vehicle motion status. When the ECU does not see this message broadcasted on the CAN network, it logs a timeout error.

• T8.275
• T8.300
• T8.390
• T8.420
• CR9090
• CX8030
• CX8040
• CX8050
• CX8060
• CX8070
• CX8080
• CX8090
• Magnum 235-340

1. 1

   Verify Equipment Configuration: Determine if the machine is actually equipped with a tachograph. If not, the Engine ECU may have been incorrectly configured.

2. 2

   Check for Related CAN Codes: Look for other CAN timeout codes (e.g., 3324 EBC1, 3325 ETC1) to rule out a broader CAN bus network failure.

3. 3

   Inspect Wiring and Power: If equipped with a tachograph, check the power and ground supply to the tachograph unit.

4. 4

   Test the CAN Lines: Probe the CAN High and CAN Low wires between the tachograph and the Engine ECU for continuity, shorts to ground, or shorts to voltage.

1. 1

   Connect diagnostic tool

   For Machines WITHOUT a Tachograph: Connect the CNH Electronic Service Tool (EST) to the machine's diagnostic port.

2. 2

   Navigate to ECU configuration

   Navigate to the Engine ECU configuration/parameters menu.

3. 3

   Disable Tachograph setting

   Locate the Tachograph (TCO) setting and change it from "Installed/Enabled" to "Not Installed/Disabled".

4. 4

   Save and clear codes

   Save the configuration, cycle the key, and clear the fault codes.

5. 5

   Check and repair power circuit

   For Machines WITH a Tachograph: If power and ground to the tachograph are missing, trace the power circuit back to the fuse panel and replace any blown fuses or repair broken supply wires.

6. 6

   Repair CAN bus wiring

   If the CAN bus wiring is damaged (chafed wires, corroded pins at the tachograph connector or ECU harness), repair the wiring using a CAN bus wiring repair kit. Ensure twisted pair integrity is maintained.

7. 7

   Replace tachograph unit

   If the wiring, power, and ground are all intact but the TCO1 message is still missing, the tachograph control unit has failed internally. Replace the tachograph unit.

8. 8

   Clear codes and verify

   Clear the fault codes using the diagnostic tool and run the engine to verify the code does not return.