Case IH 3333 – Engine ECU: Timeout of CAN Message TSC1-DR (When Active)

The Engine Control Unit (ECU) stops receiving the expected torque and speed command messages from the vehicle's main controller or transmission controller over the CAN bus while the system is in an active state, indicating a communication loss between the engine and the driveline management system.

• Case IH Magnum Series (180-340, including Series 4: 235-340)
• Case IH Steiger Series
• Case IH Farmall Series (e.g., 115U Pro EP)

1. 1

   Check for accompanying CAN timeout codes (e.g., 3332, 3334, 3336, 3338) to determine if there is a global CAN bus failure rather than a single module issue.

2. 2

   Perform a CAN Bus Resistance Test at the diagnostic connector with the key off and battery disconnected (should read approximately 60 ohms).

3. 3

   Verify that the Engine ECU and the Vehicle/Transmission Controller are receiving proper operating voltage and have clean, tight ground connections.

1. 1

   Disconnect Power

   Turn off the ignition and disconnect the negative battery cable to prevent electrical spikes.

2. 2

   Inspect Connectors

   Locate the Engine ECU and the main Vehicle/Transmission Controller. Disconnect their main harness connectors. Inspect the pins for corrosion, moisture intrusion, or pins that have pushed back into the connector body.

3. 3

   Clean and Reseat

   If minor corrosion is found, clean the pins with a high-quality electrical contact cleaner and apply dielectric grease before reseating.

4. 4

   Trace and Repair Wiring

   If the CAN resistance test failed, trace the CAN High and CAN Low wires along the chassis harness. Look for pinch points, chafing against the frame, or heat damage near the engine block. Repair any broken or shorted wires using proper solder and heat-shrink tubing.

5. 5

   Check Terminating Resistors

   If the wiring is intact but resistance is 120 ohms, locate the CAN terminating resistors (usually located at the extreme ends of the CAN backbone in the harness). Unplug and test them individually; replace any resistor that does not read 120 ohms.

6. 6

   Clear and Retest

   Reconnect the battery, turn the key on, and use a diagnostic tool (such as the CNH Electronic Service Tool - EST) to clear the inactive codes. Start the tractor and engage the driveline to ensure the code does not return.