Case IH 16116 - ATC – ATC (Automatic Temperature Control): Evaporator sensor shorted to ground.

The Automatic Temperature Control (ATC) module has detected that the voltage signal from the A/C evaporator temperature sensor has dropped to ground level. This indicates a short circuit to ground, which can be caused by a failed sensor, damaged wiring, or a faulty controller.

• MAXXUM T4E
• VESTRUM CVX
• Magnum 235-340 (Series 4)
• MX Series
• TG Series
• STX Series (280-530)
• Steiger Series (280-535, 380-530)
• 2144
• 2166
• 2188
• 2344
• 2366
• 2377
• 2388
• 2577
• 2588
• 5088
• 6088
• 7088
• 2155
• CPX420
• CPX610
• CPX620

1. 1

   Inspect the wiring harness between the ATC module and the evaporator temperature sensor for pinched wires, chafing, or damaged insulation that could be shorting the signal wire to chassis ground.

2. 2

   Disconnect the evaporator temperature sensor. If the fault code changes from ATC 116 to ATC 115 (Evaporator sensor open or shorted to power), the wiring is likely intact and the sensor has an internal short.

3. 3

   If the code remains ATC 116 even with the sensor unplugged, check for a short to ground within the wiring harness itself or an internal failure in the ATC module.

1. 1

   Power Down

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

2. 2

   Locate the Sensor

   Access the HVAC unit (typically located in the cab roof or under the seat, depending on the specific tractor/combine model) and locate the evaporator core. The temperature sensor is mounted directly on or near the evaporator coil to monitor its temperature and prevent freezing.

3. 3

   Remove the Faulty Sensor

   Disconnect the electrical connector from the evaporator temperature sensor and carefully pull/unclip the sensor from the evaporator core housing.

4. 4

   Install the New Sensor

   Insert the replacement sensor into the exact same position on the evaporator core to ensure accurate temperature readings.

5. 5

   Reconnect

   Plug the electrical connector back into the sensor.

6. 6

   Test the System

   Reconnect the battery, turn the ignition on, and clear the fault codes using the machine's diagnostic display. Run the A/C system on "Auto" to verify that the ATC 116 code does not return and the cab cools properly.