Case IH 12980 – MTA CCM & APH (Cab Control Module / Armrest): Checksum Error for parameter 27

A memory or calibration fault where the checksum validation for 'parameter 27' has failed in the module's EEPROM, indicating the control module has detected corrupted, missing, or uncalibrated data for a specific programmed parameter.

• MAXXUM T4E
• Tractors with SPS, FPS, and 16x16 HiSpec transmissions
• Tractors with Cab and CVT transmissions
• Farmall 40-45-50 series

1. 1

   Check for related EEPROM codes (12973 or 12974) which indicate a hard failure of the module's memory.

2. 2

   Verify if an EHR valve assembly was recently replaced, as replacement valves are shipped blank and trigger errors if not configured.

3. 3

   Test the front, midmount, and rear electronic remotes to isolate which valve in the stack is failing to communicate its programmed sequence.

1. 1

   Initiate Valve Renumbering

   Reprogram the number of each valve within the complete valve assembly, as the checksum error often stems from unassigned or corrupted valve sequence data.

2. 2

   Access the Reprogramming Menu

   Connect the OEM diagnostic tool (EST) and navigate to the EHR stack configuration for the MTA CCM.

3. 3

   Assign Valve Sequence

   Follow the on-screen procedure to reprogram the valve number sequence. (Note: Renumbering is only permitted on machines where electronic remotes are fitted).

4. 4

   Clear and Retest

   Once the valves are sequentially numbered and the parameters are rewritten to the EEPROM, clear the fault codes. Cycle the key and verify if code 12980 returns.

5. 5

   Module Replacement

   If the renumbering procedure fails to clear the checksum error, the internal memory of the specific EHR valve assembly or the CCM is permanently corrupted, and the physical valve/module must be replaced and subsequently programmed.