Case IH NH14905 – ACM: Keypad Missing on CAN Bus

The system has detected that the KEYPAD module is missing or not communicating on the vehicle's Controller Area Network (CAN) bus, resulting in a communication timeout error. This may prevent normal operation of the machine's control functions. This fault often points to a broader communication issue within the tractor's electronic systems, such as the Armrest Control Module (ACM) or Instrument Cluster, rather than a literal missing keypad component.

• Puma
• Magnum 215
• Magnum 245
• Magnum 275
• Magnum 305
• Magnum 335
• MX215
• MX245
• MX275
• MX305
• Steiger
• STX

1. 1

   Verify if the fault is active or stored (intermittent glitch codes can sometimes be stored during normal operation)

2. 2

   Thoroughly inspect wiring harnesses and connectors associated with the armrest control module and instrument cluster (especially behind the dashboard) for corrosion, loose pins, or physical damage

3. 3

   Check for low system voltage by ensuring the battery and charging system are functioning correctly

4. 4

   Perform an ECU reset by disconnecting the battery for several minutes to clear potential false communication errors

1. 1

   Isolate the faulty component

   Since the KEYPAD may not be a physical part, the issue is likely with the Armrest Control Module, the Instrument Cluster, or the wiring between them.

2. 2

   Test CAN bus communication

   Using a diagnostic tool, verify that all control modules are communicating properly on the CAN bus. This will help identify which specific module is not responding.

3. 3

   Inspect and test Armrest Control Module

   If the Armrest Control Module (ACM) is suspected, inspect its connectors for damage. If possible, test the module for internal faults.

4. 4

   Inspect and test Instrument Cluster

   Inspect the instrument cluster's connections. Check for internal hardware or software glitches that may require professional repair or replacement.

5. 5

   Replace faulty components

   If a component such as the Armrest Control Module or Instrument Cluster is identified as faulty, replace it with a genuine OEM part. After replacement, clear the fault codes and operate the machine to verify the repair was successful.