John Deere 170.03 – ATC (Automatic Temperature Control): Inside Air Temperature Sensor Voltage Too High / Sending Unit for Inside Air Temperature, Shorted or Open Circuit.

The controller measures an excessive voltage (over 5 volts) at the signal input of the inside air temperature sending unit (Sensor B127, typically on lead 2007). This indicates that the sensor's circuit is either shorted to a power supply lead or has an open circuit. When this code is active, automatic temperature control is restricted. The HVAC system may default to a manual mode, or the controller will attempt to estimate the inside temperature via the actual outlet air temperature sensor, leading to poor cabin temperature regulation.

• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R
• 6020 series (6120-6420, 6120L-6520L)
• 7020 series (7720, 7820, 7920)
• 8030 series (8130, 8230, 8330, 8430, 8530)
• 8230T
• 8330T
• 8430T
• E360
• E360LC

1. 1

   Visually inspect the wiring harness (specifically lead 2007) leading to sensor B127. Look for damaged insulation, pinched wires, or wires shorting against power leads.

2. 2

   Ensure that the sensor connectors are securely fastened and completely free of moisture, dirt, or corrosion, which can cause voltage irregularities.

3. 3

   Disconnect the sensor and use a multimeter to measure the voltage at the harness-side signal input. A reading consistently above 5 volts confirms a short to power.

4. 4

   If voltage is normal, test the sensor's resistance to confirm if the sensor itself has failed open.

1. 1

   Locate the sensor

   Find the inside air temperature sensor (B127) inside the cab. On many John Deere tractor cabs, this sensor is located behind the training seat or integrated into the roof/headliner trim.

2. 2

   Disconnect power

   Turn off the machine's key switch and disconnect the battery ground to prevent accidental shorts during repair.

3. 3

   Remove the faulty sensor

   Unplug the electrical connector from the sensor. Unclip or unscrew the faulty sensor from its mounting bracket.

4. 4

   Install the new sensor

   Mount the replacement sensor in the exact same orientation. Do not cover the sensor, as the ClimaTrak system relies on unobstructed ambient cab air to operate correctly in AUTO mode.

5. 5

   Reconnect and reassemble

   Plug the electrical harness back into the sensor and restore battery power.

6. 6

   System reset and function check

   Clear the stored ATC 000170.03 fault code via the cab monitor. Run the machine and engage the HVAC system in AUTO mode to verify that the cabin temperature is now regulating properly without throwing a code.