New Holland DCU 19596 – DCU: CAN receive frame EEC1 / Engine speed not in range / P0600 Serial Communication Link

The Dosing Control Unit (DCU) is failing to receive a valid engine speed signal over the SAE J1939 CAN bus network from the Engine Control Unit (ECU).

• T6
• T7
• T8
• T9
• CR9090
• CX8080
• CX8090
• FR450
• FR500
• FR600
• Magnum 235-340
• Excavators
• Wheel Loaders

1. 1

   Check Battery Voltage: Verify the battery is fully charged and providing stable power to the tractor's engine and modules.

2. 2

   Inspect CAN Bus Wiring: Check the SAE J1939 CAN bus wiring harness between the Engine ECU and the DCU for chafed wires, corrosion, or loose connections.

3. 3

   Check for Related Fault Codes: Look for engine sensor codes (e.g., E1640-03) or multiple P0600 codes indicating a compromised CAN network.

4. 4

   Software/Programming Check: Ensure no interrupted software updates have occurred, as CAN codes can log temporarily during programming.

1. 1

   Disconnect Power

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

2. 2

   Harness Inspection & Repair

   Locate the DCU and the Engine ECU. Disconnect the harness connectors and inspect the pins for corrosion, moisture, or bent terminals. Clean the contacts with electrical contact cleaner.

3. 3

   Test CAN Continuity

   Use a multimeter to test the continuity of the CAN High and CAN Low wires between the ECU and DCU. Repair or replace any damaged sections of the wiring harness.

4. 4

   Test Engine Speed Sensor

   If the wiring is intact, verify the engine speed sensor is operating correctly and sending data to the ECU, as the DCU is specifically complaining that the engine speed is 'not in range'. Replace the sensor if it is faulty.

5. 5

   Replace the DCU

   If the wiring, CAN network, and engine speed sensor are all functioning properly, the DCU itself may have suffered an internal hardware failure on its communication circuit. Replace the DCU.

6. 6

   Reprogramming

   If the DCU is replaced, it requires OEM software installation. CNH (Case New Holland) requires troubleshooting to be performed and documented before they will issue the necessary passwords for module programming.