P2002
CAUTION
DPF efficiency below threshold
The truck's control module (ECU) reports a fault on: DPF efficiency below threshold.
P2002 means a truck control module (ECU) flagged a fault on DPF efficiency below threshold, part of the Aftertreatment / DPF system on heavy-duty diesel trucks. DERATE rates it CAUTION: drive to a shop today, because the engine may cut power. Part usually replaced: DPF cleaning (or filter if cracked), $400–$4,500 (aftermarket to dealer) plus 3–6 h labor.
Aftertreatment / DPF
Can I keep driving?
Drive to a shop today. The engine may cut power (derate) if the fault stays active.
Part usually replaced
DPF cleaning (or filter if cracked)
$400–$4,500 (aftermarket to dealer)
Labor: 3–6 h
Low = bake & clean; high = new DPF
USD, part only. Labor is billed at the shop's hourly rate.
Data: DERATE verified base, updated October 2026
Related codes
Read it off your own dash
Take one photo and DERATE tells you whether you can keep driving.
Ask DERATE
DERATE assists. It does not replace inspection by a qualified technician.