Case IH 12874 – MTA CCM & APH (Cab Control Module & Armrest/Transmission Controller): CAN RX message timeout IC1

The receiving control module is experiencing a timeout because it is not receiving the expected Controller Area Network (CAN) receive (RX) messages from the Instrument Cluster 1 (IC1) within the required timeframe.

• MAXXUM T4E
• Stage V MR tractors
• Farmall 40-45-50 Tractors with Cab and CVT Transmissions

1. 1

   Verify the power and ground supply to the Instrument Cluster (IC1). If the cluster loses power, it will stop broadcasting CAN messages.

2. 2

   Check the CAN bus wiring harness between the Instrument Cluster (IC1) and the Cab Control Module (CCM) for open circuits, shorts to ground, or shorts to power.

3. 3

   Inspect the harness connectors at both the IC1 and CCM for corrosion, bent pins, or loose connections.

4. 4

   Check for other active CAN communication fault codes (such as system overvoltage/undervoltage codes 12883 or 12884) that might indicate a broader electrical or CAN bus failure.

1. 1

   Disconnect battery

   Disconnect battery power to the tractor.

2. 2

   Access modules

   Access the rear of the Instrument Cluster (IC1) and the Cab Control Module (CCM).

3. 3

   Clean connectors

   Disconnect the harness connectors and clean them with electrical contact cleaner.

4. 4

   Test continuity

   Perform a continuity test on the CAN High and CAN Low wires between the IC1 and CCM. Repair or replace the wiring harness if an open or short is found.

5. 5

   Reconnect modules

   Reconnect all modules and restore battery power.

6. 6

   Clear fault codes

   Clear the fault codes using a diagnostic tool (e.g., CNH EST).

7. 7

   Verify repair

   Turn the key on and verify if the Instrument Cluster powers up and if fault code 12874 returns.

8. 8

   Replace modules if necessary

   If the wiring is intact, power/ground is verified, and the fault persists, the Instrument Cluster (IC1) or the CCM may have an internal CAN transceiver failure and require replacement.