Case IH 14901 - ICU – ICU (Instrumentation Control Unit), ADIC, or Armrest Controller: Engine controller missing

CAN bus communication error indicating that the main vehicle network has lost communication with the Engine Control Unit (ECU). The tractor's main computer is looking for the engine controller on the data network but cannot detect it.

• VESTRUM CVX
• Puma 140
• Puma 155
• Puma 165
• Puma 180
• Puma 195
• Puma 210
• Puma 225
• Puma CVX
• Magnum MX210
• Magnum MX230
• Magnum MX255
• Magnum MX285
• Magnum 235
• Magnum 260
• Magnum 290
• Magnum 315
• Magnum 340
• Steiger 380
• Steiger 430
• Steiger 450
• Steiger 500
• Steiger 620
• Maxxum 115
• Maxxum 125
• Maxxum 140
• Farmall 115U Pro EP

1. 1

   Verify the tractor batteries are fully charged and connections are tight. Low system voltage can cause modules to drop offline.

2. 2

   Test the power supply and ground pins directly at the Engine ECU harness. If the ECU is not receiving power due to a blown fuse or broken wire, it will not boot up.

3. 3

   Disconnect the Engine ECU and inspect the pins for corrosion, moisture, or bent terminals. Clean with electrical contact cleaner if necessary.

4. 4

   Measure the resistance across the CAN High and CAN Low pins at the diagnostic port (should read approximately 60 ohms if terminating resistors are intact). Check for continuity on the CAN lines between the ICU/Armrest and the Engine ECU.

5. 5

   Look for other CAN network codes (e.g., 14900, 14904, 14905). If multiple modules are reported as missing, the issue is likely a short in the CAN bus wiring backbone rather than a failed Engine ECU.

1. 1

   Disconnect Power

   Disconnect the negative battery terminal to prevent electrical spikes.

2. 2

   Remove the ECU

   Locate the Engine Control Unit (typically mounted directly to the side of the engine block). Disconnect the main wiring harness connectors. Remove the mounting bolts and extract the faulty ECU.

3. 3

   Install the New ECU

   Mount the replacement ECU and secure the hardware. Reconnect the wiring harnesses, ensuring the locking levers click fully into place.

4. 4

   Restore Power

   Reconnect the negative battery terminal.

5. 5

   Programming and Calibration

   Connect a compatible diagnostic tool (such as Case IH EST, Jaltest, or TEXA) to the tractor's diagnostic port.

6. 6

   Flash the ECU

   Copy the configuration parameters to the new control unit, flash the correct software version for the specific tractor PIN (serial number), and perform any required engine calibrations.

7. 7

   Clear Codes

   Clear the inactive 14901 fault code from the ICU and verify that CAN communication is fully restored.