Case IH 19888 – Engine Control Module (ECM / EDC): CAN vehicle speed source and HRWS replacement defect

The Engine Control Module (ECM) is not receiving a valid High Resolution Wheel Speed (HRWS) message over the Controller Area Network (CAN) bus, or the data falls below a plausible minimum threshold.

• Tier 4b
• Case IH N-Series Loader Backhoes (TLBs)
• Case IH Magnum, Steiger, Puma, and Optum series tractors
• Case IH Flagship Combines (Axial-Flow)

1. 1

   Check for accompanying codes: Look for active wheel speed sensor faults or VCM power faults

2. 2

   Perform a CAN bus communication test to verify communication between the ECM and the VCM/Body Controller

3. 3

   Inspect the wiring harness and connectors between the VCM and ECM for shorts, open circuits, or corrosion

4. 4

   Use the Case IH Electronic Service Tool (EST) to monitor live data from individual wheel speed sensors while the machine is moving

1. 1

   Resolve Base Sensor Faults

   If diagnostic checks reveal a faulty individual wheel speed sensor, replace the sensor and inspect its localized wiring harness.

2. 2

   Repair CAN Wiring

   If the sensors are reading correctly but the ECM still isn't receiving the HRWS message, repair or replace any damaged CAN bus wiring or corroded pins at the ECM or VCM connectors.

3. 3

   VCM Reprogramming/Replacement

   If the wiring is intact and the VCM is receiving good sensor data but failing to broadcast the HRWS message on the CAN network, the VCM/Body Controller may require a software flash/reprogramming or complete replacement.

4. 4

   Clear and Test

   Connect the Case IH Electronic Service Tool (EST), clear the pending and active fault codes, and test drive the machine to verify that the vehicle speed is correctly displayed on the dash and the code does not return.