New Holland DCU 19605 – DCU (Dosing Control Unit): CAN receive frame ET1 (Oil and Water temp engine) _timeout _P0600 Serial Communication Link.

This code indicates a CAN bus communication timeout. The Dosing Control Unit (DCU) relies on the Engine Control Unit (ECU) to broadcast the "ET1" data frame, which contains the engine oil and water temperature readings. The DCU needs this temperature data to properly calculate and inject Diesel Exhaust Fluid (DEF/Urea) into the exhaust system. When the DCU does not receive this message within the expected timeframe, it logs a timeout error alongside a generic P0600 (Serial Communication Link) fault.

• T7.210
• T7.260
• T8 Series
• CR6090
• CR8090
• CR9090
• CX8070
• CX8090
• LM6.32
• LM7.42

1. 1

   Inspect the CAN bus wiring harness connecting the Engine ECU to the DCU for chafed wires, melted insulation, or pinch points.

2. 2

   Disconnect the connectors at both the DCU and the Engine ECU to check for moisture, corrosion, or pushed-back pins.

3. 3

   With the battery disconnected, measure the resistance across the CAN High and CAN Low lines to ensure the circuit is intact (standard CAN network resistance is typically 60 ohms).

4. 4

   Verify that the engine oil and water temperature sensors are working and sending valid data to the Engine ECU (if the ECU has no data, it cannot broadcast the ET1 frame).

5. 5

   Use the CNH Electronic Service Tool (EST) to verify if the Engine ECU is successfully broadcasting the ET1 frame on the network.

1. 1

   Read fault codes

   Connect the CNH Electronic Service Tool (EST) to the machine's diagnostic port to read all active and stored fault codes. Check if other P0600 communication codes are present, which would indicate a broader CAN bus failure.

2. 2

   Perform diagnostic checks

   Perform the visual and multimeter diagnostic checks on the wiring harness between the Engine ECU and the DCU.

3. 3

   Clean connectors

   Clean the connector contacts with electrical contact cleaner and apply dielectric grease. Reconnect the harness securely.

4. 4

   Repair or replace wiring

   If a wiring fault (open or short circuit) is found, repair or replace the affected section of the CAN bus harness.

5. 5

   Replace DCU

   If the wiring is perfectly intact, the connectors are clean, and the Engine ECU is confirmed to be transmitting the ET1 frame, the Dosing Control Unit (DCU) itself has likely suffered an internal communication failure and must be replaced.

6. 6

   Program new DCU

   If the DCU is replaced, the new module will require software installation and calibration using the CNH EST before the machine will operate correctly.