Case IH 16111 – ATC (Automatic Temperature Controller): Cab sensor open or shorted to power

The control module has detected a voltage reading from the cab interior temperature sensor (return air sensor) that is out of normal range, specifically pointing to an open circuit (such as a disconnected plug or broken wire) or a short circuit to a power source.

• Puma/Mid Range Magnum
• Maxxum
• Case IH Magnum series
• Case IH Puma series
• Case IH Steiger series
• Case IH Axial-Flow series

1. 1

   Locate the cab temperature sensor in the return air ducting (often below or behind the operator's seat).

2. 2

   Visually inspect the sensor connections and the wiring harness for visible damage, loose fitment, or corrosion.

3. 3

   Test the sensor wiring harness for continuity to ensure there is no open circuit.

4. 4

   Test the wiring for a short to a 12V power source.

5. 5

   Check the ATC controller power supply and ground connections to rule out a module-side issue.

6. 6

   If the wiring is intact and no shorts are found, the cab temperature sensor itself has likely failed internally.

1. 1

   Power Down

   Turn off the machine and disconnect the battery ground to prevent electrical spikes during repair.

2. 2

   Access the Sensor

   Remove the necessary cab interior trim panels or seat base covers to access the ATC return air/cab temperature sensor.

3. 3

   Disconnect and Inspect

   Unplug the sensor connector. Inspect the pins on both the harness side and the sensor side. Clean any corrosion with electrical contact cleaner.

4. 4

   Repair Wiring (If Applicable)

   If your diagnostic tests revealed a broken wire or chafed insulation causing a short to power, splice and repair the damaged section of the harness.

5. 5

   Replace Sensor (If Applicable)

   If the harness is good, remove the faulty cab temperature sensor from its mounting grommet/bracket and install the new OEM replacement sensor.

6. 6

   Reassemble

   Plug the sensor back into the harness and reinstall all cab trim panels.

7. 7

   Clear Codes

   Reconnect the battery, turn the key to the ON position, and use the machine's display or an Electronic Service Tool to clear the fault codes.

8. 8

   Test Operation

   Run the HVAC system to ensure the ATC regulates cab temperature properly and the code does not return.