John Deere Fault Code

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3216.2

Yellow CEL; Potential derate; DPF regens becoming frequent.

System

ECU

Symptom

Yellow CEL; Potential derate; DPF regens becoming frequent.

Diagnosis & fix steps

Inlet NOx Sensor Drifted High. LOGIC: The sensor signal is "out of bounds" for the current engine load/exhaust flow. ACTION: 1. Check exhaust for leaks upstream of the sensor. 2. Verify DEF dosing is occurring. FIX: Replace the Inlet NOx Sensor.

Red Seal field insights

These sensors are "consumables." If the machine has over 4,000 hours, they are likely just tired. Always replace the sensor and the module (it comes as one unit).

Same code keeps coming back?

That's a program problem, not a part problem. Book a 30-minute uptime review with Grant, a Red Seal Heavy Duty Technician.

Book an uptime review

Read before you touch anything

  • This is general reference information, not a repair manual. It is for trained, qualified technicians.
  • Fault codes, meanings and procedures vary by model, serial number and software version. Confirm the code and the procedure against the manufacturer's service manual before acting.
  • Follow the OEM service manual, torque specs and your site's safety procedures: lockout/tagout, block raised equipment, relieve hydraulic, fuel and air pressure, and let hot systems cool.
  • You use this information at your own risk. Adventure Mechanical and AM Fleet Integrity accept no liability for damage, injury, downtime or loss arising from its use.
  • Not affiliated with or endorsed by any manufacturer. Brand names are used only to identify the equipment a code applies to.

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