Case IH 3171 – Vehicle Control Module (VCM), Transmission Control Unit (TCU), or Engine Control Module (ECM / EDC): CAN transmit error - EEC2 message (Electronic Engine Control 2 message)

The control module is either failing to transmit or failing to receive vital throttle and load data (EEC2 message) over the CAN bus network.

• 580N
• 580 Super N
• Maxxum
• Puma
• Optum
• Magnum

1. 1

   Measure the resistance across the J1939 CAN High and CAN Low pins with the battery disconnected (should read approximately 60 Ohms).

2. 2

   Inspect the CAN bus wiring harness between the VCM/TCU and the Engine Controller for chafing, corrosion, or backed-out pins.

3. 3

   Verify that other J1939 devices or hydraulic solenoids are not causing electromagnetic interference that is loading down or inhibiting CAN communication.

4. 4

   Check the accelerator pedal potentiometer (throttle position sensor) for dead spots, correct voltage supply, and proper calibration.

5. 5

   Use the Case IH Electronic Service Tool (EST) or DATAR to scan for companion CAN communication codes (such as 3179 or 3180) which might indicate a broader network failure.

1. 1

   Connect Diagnostic Tool

   Connect the Case IH Customer EST (Electronic Service Tool) to the machine's diagnostic port to retrieve all active and stored fault codes.

2. 2

   Inspect and Repair Wiring

   If the CAN network resistance is out of spec (e.g., 120 Ohms or open circuit), locate and repair the break in the CAN-Bus wire harness or replace the missing/damaged terminating resistor.

3. 3

   Test the Potentiometer

   If the wiring is intact, test the accelerator pedal potentiometer. If the sensor is failing to read the pedal position, the VCM cannot generate the EEC2 message.

4. 4

   Replace Faulty Component

   Replace the damaged CAN harness section or the faulty accelerator pedal position sensor.

5. 5

   Recalibrate and Clear

   If the pedal sensor was replaced, perform the accelerator pedal learning routine via the EST. Clear the fault codes, cycle the ignition, and run the engine to verify the 3171 code does not return.