Generic Fault Code
Free · no signupP2002
DPF Warning Lamp / Low Fuel Economy
System
Emissions / DPF
Symptom
DPF Warning Lamp / Low Fuel Economy
Diagnosis & fix steps
LOGIC: Diesel Particulate Filter Efficiency Below Threshold (Bank 1).
ACTION: Inspect the tailpipe for black soot residue (indicating a cracked DPF substrate). Inspect differential pressure sensor hoses for cracks, splits, or loose clamps.
Red Seal field insights
Substrate Integrity: A clean tailpipe with no soot indicates the DPF filter is intact; if the differential pressure drop across the filter is too low under exhaust flow, the PCM assumes a hollowed or cracked substrate.
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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