Case IH 19849 – ECM: TSC1 CAN Timeout to ECM

The Engine Control Module (ECM) is expecting a Torque/Speed Control 1 (TSC1) message from the Body Computer (VCM) over the Controller Area Network (CAN), but the message is not arriving within the expected timeframe. This indicates a CAN communication failure between the modules.

• Tier 4b
• Magnum
• Steiger
• Puma
• Optum
• 580N
• 590SN
• T7
• T8

1. 1

   Check for other active CAN bus fault codes (e.g., 12011, 3335, 3339) that might indicate a broader network issue rather than an isolated module failure.

2. 2

   Inspect all major cab and engine ground connections to ensure they are clean and tight, as poor grounds frequently cause CAN communication drops.

3. 3

   With the battery disconnected, measure the resistance across the CAN High and CAN Low pins at the diagnostic port (should read approximately 60 ohms).

4. 4

   Inspect the wiring harness between the Body Computer and the Engine ECM for chafing, cuts, or corrosion, particularly under the cab or near the engine block.

1. 1

   Verify the fault

   Connect the CNH Electronic Service Tool (EST) to verify code 19849 is active and check the status of the Body Computer and ECM on the CAN network.

2. 2

   Inspect connectors

   Disconnect the harness connectors at both the Engine ECM and the Body Computer. Inspect the pins for corrosion, moisture ingress, pushed-back pins, or poor pin tension. Clean and apply dielectric grease if necessary.

3. 3

   Check and replace CAN terminators

   Locate the CAN bus terminating resistors. If they are the older style or test out of specification (causing noise or signal bounce), replace them with updated CNH terminators.

4. 4

   Repair wiring

   If the CAN bus resistance test indicates a short (near 0 ohms) or an open circuit (120 ohms), trace the CAN High (yellow) and CAN Low (green) wires between the modules and repair the damaged section of the harness.

5. 5

   Module substitution

   If the wiring, grounds, and terminators all test perfectly (2.5V on CAN High and 2.4V on CAN Low) and the code persists, replace the Body Computer (VCM) or Engine ECM as a last resort.

6. 6

   Clear and test

   Reconnect all components, clear the fault codes using the EST, and test operate the machine (specifically functions requiring torque/speed management) to verify the repair.