New Holland DCU 19607 – DCU (Dosing Control Unit): CAN receive frame ET1 (Oil and Water temp engine) | SAE J1939 Check for CAN receive signal : (Water temperature not in range) | P0600 Serial Communication Link

This indicates a CAN bus communication error. The Dosing Control Unit (DCU) is expecting to receive the 'ET1' (Engine Temperature 1) data frame over the SAE J1939 network from the Engine Control Module, but the water (coolant) temperature signal is either missing, timed out, or reporting a value that is 'not in range'. This triggers a P0600 Serial Communication Link failure.

• New Holland T7 Series
• New Holland T8 Series

1. 1

   Use a diagnostic scan tool to check the live engine coolant temperature reading directly from the Engine ECU to see if it is out-of-range.

2. 2

   Look for other active CAN communication codes (such as other P0600 or timeout codes) to determine if there is a broader J1939 CAN bus network failure.

3. 3

   Check the SAE J1939 CAN bus wiring harness and connectors between the Engine ECU and the DCU for continuity, shorts to ground, corrosion, or backed-out pins.

1. 1

   Test the Coolant Temperature Sensor

   If the live data shows an erratic or out-of-range water temperature, inspect the engine coolant temperature sensor and its pigtail connector. Test the sensor's resistance. If it fails, replace the sensor.

2. 2

   Inspect and Repair the CAN Harness

   If the sensor is functioning properly and the Engine ECU shows the correct temperature, physically trace the CAN bus wiring from the Engine ECU to the DCU. Repair any chafed wires or clean corroded connector terminals on the J1939 link.

3. 3

   Test the DCU

   If the wiring is fully intact, the sensor is good, and the DCU still fails to receive the ET1 frame, the DCU may have suffered an internal communication failure.

4. 4

   Replace and Reprogram

   If the DCU is deemed faulty, replace the module. Note: Installing a new DCU requires OEM software installation and programming; it is not a plug-and-play component.

5. 5

   Clear Codes

   Clear the fault codes using a diagnostic tool and run the machine to operating temperature to verify the repair.