Case IH 2477 (190.19) - DEC – TCU / EPC / DEC: CAN Communication Error - Invalid Engine Speed / Incorrect CAN BUS Message, Engine Speed from ECU

This diagnostic trouble code is generated when the Engine Control Unit (ECU) cannot determine the engine speed and therefore cannot provide the CAN BUS with valid data. Because the ECU broadcasts an invalid or replacement value over the CAN network, the receiving modules flag this as a communication error. The documentation notes that this code can also be triggered simply if the engine stalls.

• MAXXUM T4E
• VESTRUM CVX
• Farmall 85C
• Farmall 95
• Farmall 105U
• Farmall 110A
• Maxxum 110
• Maxxum 115
• Maxxum 120
• Maxxum 125
• Maxxum 130
• Maxxum 140
• Maxxum 150
• Puma 130
• Puma 140
• Puma 150
• Puma 165
• Puma 185
• Puma 200
• Puma 215
• STX280
• STX330
• STX380
• STX430
• STX480
• STX530
• Optum Series
• Luxxum Series

1. 1

   Check for Engine Stalling: Verify if the engine simply stalled during operation, as an abrupt stall will trigger this code without any actual component failure.

2. 2

   Check Engine ECU Codes: Scan the Engine ECU for primary fault codes. Since the ECU code takes priority, look for codes specifically pointing to the Engine Speed Sensor (Crankshaft Position Sensor) circuit (e.g., open circuit, short to ground, or voltage too high/low).

3. 3

   Inspect Wiring and Connections: Inspect the wiring harness between the Engine Speed Sensor and the Engine ECU. Look for chafed wires, loose pins, or corrosion that could interrupt the sensor's signal to the ECU.

4. 4

   Verify CAN Bus Integrity: Ensure the CAN communication lines between the Engine ECU and the TCU/DEC are intact and not shorting out.

1. 1

   Address Primary ECU Faults

   If the Engine ECU is reporting a primary speed sensor fault, proceed to replace the Engine Speed Sensor (Crankshaft Position Sensor).

2. 2

   Locate the Sensor

   Locate the Engine Speed Sensor on the engine block (typically reading off the crankshaft or flywheel tone ring).

3. 3

   Replace the Sensor

   Disconnect the wiring harness, remove the retaining bolt, and pull the old sensor. Install the new OEM sensor and torque to the manufacturer's specification. Reconnect the harness.

4. 4

   Clear Codes

   Use a diagnostic tool (such as the CNH Electronic Service Tool) to clear the fault codes from both the Engine ECU and the TCU/DEC.

5. 5

   Test Operation

   Start the engine and verify that the engine RPM is reading correctly on the dash and diagnostic tool. Test drive the machine to ensure the 190.19 CAN communication error does not return.