John Deere 003673.03 – ECU: Exhaust Throttle Sensor Calibration Issue

The Engine Control Unit (ECU) has detected an issue with the calibration of the exhaust throttle sensor, which is likely integrated into the exhaust throttle valve assembly. The FMI .03 indicates a 'Voltage Above Normal, or Shorted to High Source' condition, meaning the ECU is receiving an electrical value outside the expected range. Because the ECU cannot verify the valve's position, it cannot properly control the variable geometry turbocharger (VGT), which can lead to poor engine performance, increased emissions, and potential component damage.

• 650K Crawler Dozer
• 550K Crawler Dozer
• 130G Excavator
• 310SK
• 5100MH
• 6100 RC
• 3025E
• 3032E
• 3038E
• 4044M
• 4044R
• 4052M
• 4052R
• 4066M
• 4066R
• PowerTech 4.5L (4045HFL92, 4045HFC92, 4045HFG92, 4045HT070)

1. 1

   Visually inspect the exhaust throttle valve and actuator for physical damage or sticking. Manually check if the valve moves freely if safe to do so.

2. 2

   Inspect the wiring harness and connector going to the exhaust throttle valve actuator for corrosion, damage, pinched wires, or loose pins (looking for a short circuit).

3. 3

   Scan for any other active or stored fault codes, particularly those related to sensor supply voltage or CAN bus communication.

4. 4

   Check the voltage at the connector pins for the sensor (e.g., 24-volt supply, ground, and 2.5 volts on CAN wires) to confirm if there is a short to a high voltage source.

1. 1

   Repair wiring

   If diagnostic checks reveal a wiring issue or short circuit, repair the harness or connector first. Clear the codes and see if the fault returns.

2. 2

   Replace exhaust throttle valve

   If the wiring is intact and the valve is suspected to be faulty, replace the exhaust throttle valve assembly, which typically includes the actuator and sensor.

3. 3

   Calibrate new valve

   After replacing the exhaust throttle valve or its actuator, perform a mandatory calibration using John Deere Service ADVISOR diagnostic software. Select 'VGT/Exhaust Throttle Valve Actuator - Calibration' with the machine in a key-on, engine-off state to allow the ECU to learn the new valve's end-of-travel positions.