DPF / Aftertreatment Diagnostics
DPF Regen & DEF/SCR Aftertreatment Diagnostics
Aftertreatment faults are one of the most common reasons a truck derates. A forced or stationary regeneration can be the right step — or it can mask the real problem, or be unsafe. We diagnose why the system is flagging, check the manufacturer's prerequisites, and only run a supported stationary regeneration when the checks say it's appropriate.
Calls accepted 24/7. On-site dispatch subject to technician availability and safe service conditions.
Common aftertreatment complaints
- DPF lamp on, or a message asking for a parked / stationary regen
- Regen won't start, keeps aborting, or the soot level won't come down
- DEF quality, DEF dosing, or DEF level warnings
- SCR efficiency or NOx sensor faults
- Derate countdown or speed limit tied to aftertreatment faults
- High exhaust back-pressure or differential-pressure readings
What the visit covers
Root-cause diagnosis first
We review soot/ash load, differential pressure, exhaust temperatures, sensor plausibility and regen history to find out why the DPF is loading or why a regen isn't completing.
DEF / SCR troubleshooting
DEF quality and dosing checks, NOx sensor data, SCR efficiency faults and related heaters and lines, as supported by the vehicle and software.
OEM prerequisite checks
Before any stationary regeneration: active faults that block regen, fluid levels, coolant temperature, parking-brake and neutral requirements, and a safe location away from combustibles.
Supported stationary regeneration
Performed only when the vehicle and software support it, prerequisites are met, the area is safe, and the diagnosis says a regen is the appropriate step.
- Not every aftertreatment fault is fixed by a regen. If it's a sensor, injector, EGR or DEF problem, or a DPF that needs cleaning or replacement, we'll tell you exactly what it is and help get it handled.
- We won't run a regeneration if the prerequisites fail, a regen-blocking fault is active, or the location isn't safe — exhaust temperatures during a regen are very high.
- We do not delete, defeat, tune out or bypass emissions equipment or aftertreatment derates.
Questions about this service
Can you perform a forced DPF regen?
Only if it's supported by the vehicle and our software and it's safe after the OEM prerequisite checks. Not every fault can be fixed by a regen, so we diagnose first.
Where does the truck need to be for a stationary regen?
Parked on a safe, level surface, clear of grass, fuel, debris and anything combustible near the exhaust, with room to work. If the location isn't safe, we won't run it — tell us exactly where the truck is when you call.
Can you remove a DEF or DPF derate?
We diagnose the fault that caused the derate. When the cause is fixed or a supported procedure resolves it, the derate typically clears as designed. We don't bypass or disable derates.
Related services
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On-site fault-code retrieval, live data analysis and troubleshooting for supported commercial vehicles.
DetailsEngine Derate & No-Power Diagnostics
Investigate warning lamps, limp mode, reduced power, and drivability concerns. No promises of immediate derate removal.
DetailsECM / TCM & Network Diagnostics
Module communication and electronic system diagnosis, subject to vehicle coverage and authorized software functions.
DetailsTruck down or throwing codes?
Call with the truck's year, make, model, engine, the fault messages and your exact location. We'll tell you honestly whether we can help and when.
Calls accepted 24/7. On-site dispatch subject to technician availability and safe service conditions.