DPF, AdBlue and SCR
Why will DPF regeneration not start or finish?
A DPF requesting regeneration that will not start or repeatedly stops does not automatically need replacement. First establish whether the machine permits regeneration and its conditions are met. Then check sensors, exhaust heating and calculated DPF loading.
Regeneration conditions
Conditions vary by machine. The controller usually considers engine temperature, fuel level, critical faults, control positions, neutral and parking brake, exhaust temperature, DPF condition and machine interlocks. One unmet condition can leave the button unresponsive. Read the display message and service parameters first.
When manual regeneration is still permitted
Only if the manual permits stationary or manual regeneration, park safely, warm the engine, meet the manufacturer’s conditions and start the normal display or button procedure. Exhaust temperatures become very high. Do not regenerate near dry grass, fuel or combustible materials.
DPF differential pressure sensor
Incorrect sensor or tube readings can mislead the ECM about filter condition. Check the sensor, both tubes, blockage, cracks, condensation, engine-off reading and how pressure changes with engine speed.
Exhaust temperature sensors
The system must see and control temperature at the required points. A faulty sensor can block regeneration, interrupt it or cause incorrect dosing.
DOC, DPF and fuel dosing
Burning soot requires the correct temperature. Check DOC, exhaust fuel injector or doser if fitted, fuel supply, ignition plug or system where applicable, exhaust leaks and DPF condition. If fuel is supplied but temperature does not rise, find the cause rather than restarting regeneration repeatedly.
Why regeneration starts but does not finish
Possible reasons include failure to reach temperature, a wrong temperature reading, excessive soot load, ash as well as soot, an engine fault producing more soot, operator interruptions or low-load and unsuitable operation.
Excessive loading
Beyond a certain loading level, the system may prohibit normal regeneration to protect the machine. Do not keep pressing the button. Read parameters, codes and the manufacturer’s procedure; service regeneration or DPF removal and cleaning may be needed.
Find the reason for soot production too
Even after successful regeneration, the problem returns if the engine smokes, has a faulty injector, lacks boost, has faulty EGR, runs too cold or idles for long periods.
What you can observe
What exactly does the display say? Is regeneration permitted, is the engine warm and are there faults? What is the soot load? Does the process start, and when does it stop? Do exhaust temperatures rise, and is there heavy smoke or power loss?
Related problems
Further service support
Have a fault code?
Problem still there?
If these checks have not identified the cause or the fault returns, contact TSV Servis. The more initial information you provide, the sooner we can identify the next diagnostic direction.
What to send us
Send the machine model, S/N, engine, fault codes, soot load, differential pressure, EGT temperatures, regeneration history and regeneration permission status.
Include the make and model, S/N or a nameplate photo, engine model if known, operating hours, exact code or display photo and when the fault occurs.
Also tell us what you have already checked or replaced and the results. Include a photo or short video of the symptom where useful.
+420 722 307 850 · tsvcz@seznam.cz