FAW Fault Code
Free · no signupSPN 3226 FMI 04
Amber Emission Lamp / 30% Power Cut
System
Aftertreatment
Symptom
Amber Emission Lamp / 30% Power Cut
Diagnosis & fix steps
LOGIC: Outlet NOx Sensor Heating Element Short to Ground.
ACTION: Disconnect downstream NOx sensor at exhaust pipe outlet. Test heater power supply fuse in chassis distribution box; measure sensor heater circuit resistance. Replace smart NOx probe head.
Red Seal field insights
Thermal Shock & Water Spray: Mounting the NOx sensor near the rear wheel splash path exposes the hot ceramic element to sudden cold road puddle splash, cracking the internal ceramic heater core.
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.
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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