Case IH 19345 – Engine Control Module (ECM) or SCR Control Module: Timeout error of CAN receive frame HCUData

The Engine Control Module (ECM) or SCR controller is not receiving the expected CAN bus communication messages from the Heater Control Unit (HCU) within the required timeframe. The HCU is responsible for managing the heating of the Diesel Exhaust Fluid (DEF) / AdBlue system to prevent it from freezing.

• Tier 4b
• Tier 4 Final
• Magnum
• Maxxum
• Puma
• Steiger
• Vestrum
• Farmall
• Axial-Flow combines
• Patriot sprayers
• Titan sprayers
• 580N backhoe loaders
• 580SN backhoe loaders
• SV-series skid steers

1. 1

   Inspect the CAN bus wiring harness connecting the Heater Control Unit (HCU) to the ECM/SCR controller for physical damage

2. 2

   Ensure the CAN cable is fully seated and not disconnected or broken at the connectors

3. 3

   Use a multimeter to check for short circuits in the HCU wiring

4. 4

   Verify the Heater Control Unit is receiving proper 12V/24V power and has a solid ground connection

1. 1

   Repair Wiring

   If the diagnostic checks reveal a broken wire, disconnected plug, or short circuit in the CAN bus harness, repair or replace the affected wiring section.

2. 2

   Replace the HCU

   If the wiring harness, power, and ground are all confirmed to be in good working order but the CAN timeout error persists, the Heater Control Unit itself has failed internally.

3. 3

   Install New Unit

   Remove the defective HCU and install the replacement unit.

4. 4

   Clear Codes

   Connect an Electronic Service Tool (EST) to clear the fault codes and verify that CAN communication between the HCU and ECM has been restored.