Case IH 1053 – Engine Control Unit (ECU / EDC) or Machine Controller: Timeout of CAN Message CM1BC

This code indicates a communication failure on the Controller Area Network (CAN) bus. Specifically, the expected "CM1BC" data frame/message has timed out, meaning the receiving module did not get the required signal from the transmitting module within the programmed time window. This triggers an Amber telltale warning lamp.

• skid steer
• Tractors
• Magnum
• Puma
• Steiger
• Farmall
• Maxxum
• Skid Steer Loaders (SSL)
• Compact Track Loaders (CTL)

1. 1

   Verify battery voltage and grounds to the ECU, as high or low battery voltage can disable power stage diagnosis and disrupt CAN communication.

2. 2

   With the battery disconnected, perform a CAN Bus Resistance Test by measuring the resistance across the CAN High and CAN Low pins at the diagnostic port (a healthy CAN bus should read approximately 60 ohms).

3. 3

   Inspect the communication BUS wiring between the engine controller and the machine controller/instrument cluster for chafing, cuts, or pinch points.

4. 4

   Inspect the connectors at the Engine ECU and the Machine Controller for moisture, corrosion, or pushed-back pins.

1. 1

   Disconnect Power

   Disconnect the negative battery cable before servicing the CAN bus to prevent module damage.

2. 2

   Clean and Reseat Connectors

   Disconnect the main harnesses at the Engine ECU and the Machine Controller. Spray the pins with electrical contact cleaner, ensure no pins are bent or pushed out of the connector body, and firmly reconnect them.

3. 3

   Repair Wiring

   If the resistance test indicated a short or open circuit, trace the CAN bus harness between the cab and the engine. Repair any broken wires by soldering and applying heat-shrink tubing.

4. 4

   Replace Terminating Resistors

   If the CAN bus resistance measured 120 ohms and the wiring is intact, locate and replace the faulty CAN bus terminating resistor (usually located at the extreme ends of the CAN network, sometimes near the air filter or behind the cab controllers).

5. 5

   Clear Codes

   Reconnect the battery. Use the CNH Electronic Service Tool (EST / DPA5) to clear the inactive fault codes.

6. 6

   Module Replacement (Last Resort)

   If the wiring and resistors are perfectly intact but the CM1BC timeout persists, the internal CAN transceiver in either the Engine ECU or the Machine Controller has failed. The faulty module will need to be replaced and programmed by a dealer.