Case IH 2296 – Master Controller, Instrument Cluster (IC), or Vehicle Control Module (VCM): UCM Absent on CAN2

Controller Area Network (CAN) communication failure. The Universal Control Module (UCM) is failing to broadcast its expected data or 'heartbeat' messages over the CAN2 network bus, indicating it is offline or missing.

• MAXXUM T4E
• Magnum AFS Connect
• Steiger AFS Connect
• Puma series
• Maxxum series
• Axial-Flow series (5130, 6130, 7130, 8000, 9900)
• 2000 Series Early Riser

1. 1

   Measure network termination resistance across the CAN2 High and CAN2 Low pins at the diagnostic port (should read exactly 60 ohms).

2. 2

   Verify that the fuses and relays supplying power to the UCM are intact.

3. 3

   Visually inspect the CAN2 harness and bulkhead connectors for damage, bent pins, pushed-out terminals, corrosion, or broken wires.

1. 1

   Power Down

   Turn the key OFF and disconnect the battery via the master disconnect switch.

2. 2

   Isolate the UCM

   Locate the Universal Control Module. Unplug the main harness connectors from the UCM.

3. 3

   Check Connector Integrity

   Inspect the UCM pins for moisture, corrosion, or thermal damage. Clean with electrical contact cleaner if minor corrosion is present.

4. 4

   Verify Voltage

   Reconnect the battery and turn the key ON. Using a multimeter, verify that the UCM connector is receiving battery voltage (12V) on its main power pins and switched ignition power pins, and that the ground pins have continuity to the chassis.

5. 5

   Test CAN Lines

   Turn the key OFF. Measure the continuity of the CAN2 High (often a yellow wire) and CAN2 Low (often a green wire) circuits from the UCM connector back to the main bulkhead or diagnostic connector.

6. 6

   Repair or Replace

   If a wire is broken or shorted, repair the harness using a CNH approved wiring repair kit. If power, ground, and CAN wiring all test perfectly but the UCM remains 'absent,' the UCM has failed internally.

7. 7

   Module Replacement

   Install the new UCM. Note: A new UCM is blank and must be flashed/programmed and calibrated to the specific machine using the Case IH Electronic Service Tool (EST) laptop software.