Case IH 17585 (F-518665-09) - ECU – Engine Control Unit (ECU): CAN communication failure between vehicle controller and ECU controller - TSC1_VR message (Engine brake)

The Engine Control Unit (ECU) has stopped receiving or is receiving corrupted data from the machine's main vehicle controller (CCU or UCM) regarding the TSC1_VR CAN message.

• VESTRUM CVX
• Case IH 240 Series Axial-Flow Combines (7240, 8240, 9240)
• Case IH Magnum Tractors (180-380)
• Case IH Steiger Tractors (370-620)

1. 1

   Check for other active vehicle CAN faults. If related CAN faults exist, they must be resolved first, as they may be pulling the network down.

2. 2

   Check ECU Supply Voltage: Turn the ignition switch to the ON position, disconnect the vehicle (VE) harness from the ECU A-095 at connector X-911, and use a multimeter to check for voltage on the vehicle (VE) harness side.

3. 3

   Check Pin Voltage Specifications at Connector X-911: From X-911 pin 1, wire 6408B (GN) to chassis ground should read 12.0 V.

4. 4

   Check Pin Voltage Specifications at Connector X-911: From X-911 pin 25, wire 6408C (GN) to chassis ground should read 12.0 V.

5. 5

   Check Pin Voltage Specifications at Connector X-911: From X-911 pin 26, wire 6408D (GN) to chassis ground should read 12.0 V.

6. 6

   Identify Potential Failure Modes: external power supply connected improperly, faulty charging system, faulty solenoid, faulty wire harness, or a faulty Central Control Unit (CCU) / Universal Control Module (UCM).

1. 1

   Battery & Charging System Verification

   Test the machine's batteries and alternator to ensure a steady 12.0V+ supply, as voltage drops can disrupt CAN communication.

2. 2

   Harness Inspection

   Inspect the CAN bus wiring harness between the CCU/UCM and the Engine ECU. Look for chafing, pinched wires, or corrosion, paying special attention to connector X-911.

3. 3

   Perform Pin Tests

   Execute the voltage checks at connector X-911 as outlined in the diagnostic steps.

4. 4

   Repair Wiring

   If the 12.0V supply is missing at pins 1, 25, or 26, trace the respective wires back to the power distribution center or CCU to locate and repair the open circuit or short.

5. 5

   Module Replacement

   If the wiring harness is intact, the CAN bus lines show proper resistance (typically 60 ohms across the network), and all voltages are correct, the communication failure is internal. You will need to replace either the CCU/UCM or the Engine ECU.

6. 6

   Reprogramming

   Any replaced control module must be flashed and calibrated by an authorized Case IH dealer using the Electronic Service Tool (EST) to sync with the machine's CAN network.