Case IH 2725 – ZTC (Zone Tractor Controller): ZTC - CAN message EEC2 timeout

Communication failure on the tractor's Controller Area Network (CAN) bus. The ZTC is expecting to receive the EEC2 (Electronic Engine Controller 2) message from the Engine Control Unit (ECU), but the message is not arriving within the programmed time threshold.

• Steiger T4B
• Case IH Steiger (AFS Connect)
• Case IH Magnum and Puma series
• Case IH Farmall series

1. 1

   Check for accompanying CAN timeout codes (e.g., CCVS, ERC1, TSC1) to determine if the entire CAN bus is compromised.

2. 2

   Inspect the wiring harness and connectors between the Engine ECU and the ZTC for chafed wires, broken pins, or corrosion.

3. 3

   Perform a CAN Bus Resistance Test at the diagnostic port with the battery disconnected (should read approximately 60 ohms; 120 ohms indicates a broken wire or failed terminating resistor, 0 ohms indicates a short circuit).

4. 4

   Verify that the Engine ECU is receiving proper voltage and has a solid ground, as intermittent power loss stops message broadcasting.

5. 5

   Ensure there is no electromagnetic interference (EMI) on the CAN bus caused by aftermarket equipment or damaged shielding.

1. 1

   Disconnect Power

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

2. 2

   Clean Connections

   Disconnect the harness at the ZTC and the Engine ECU. Use electrical contact cleaner to clean the pins. Check for pushed-back pins or spread terminals and correct them if necessary.

3. 3

   Repair Harness

   If the diagnostic tests revealed a short or open circuit in the CAN wiring, locate the damaged section of the harness. Splice and solder the wires, sealing them with heat-shrink tubing to prevent moisture ingress.

4. 4

   Software Update

   If the wiring tests perfectly, connect the CNH Electronic Service Tool (EST). Check if there is a software mismatch or an available firmware update for the ZTC or Engine ECU. Flash the modules to the latest software version.

5. 5

   Module Replacement

   If the wiring is intact, the software is up to date, and the Engine ECU is confirmed to be broadcasting properly, the ZTC module has failed internally and must be replaced. (Conversely, if the Engine ECU is failing to broadcast any messages, the Engine ECU must be replaced).

6. 6

   Clear Codes and Calibrate

   Reconnect the battery, clear the inactive fault codes using the diagnostic tool, and perform a test drive to ensure the EEC2 timeout does not return.