IVS 360 from Opus IVS is backed by over 100 OE-certified master technicians delivering live diagnostic repair guidance. Here, we follow the team as they diagnose a vehicle displaying a DPF warning light on the instrument panel cluster, along with the pre-glow warning light.
Symptoms:
- DPF warning light on together with pre-glow warning light.
- Loss of power.
- Engine Management light on.
Fault Codes:
- P2002 (8194) Particle filter bank 1 malfunction ECM – ECM
- P242F (9263) Particle filter maximum load exceeded ECM – ECM
Cause:
- High soot loading in the diesel particulate filter (DPF).
Repair step-by-step
1
Read the fault memory of engine ECM.
2
If no fault is logged, and only the DPF light is on, then the vehicle needs DPF regeneration.
a. The DPF light does not signify a fault with the vehicle but means that the vehicle has not managed to regenerate the DPF due to frequent short journeys, stop/start trips or insufficient exhaust gas flow.
b. To regenerate the DPF, change to a driving profile as described in the owner’s manual.
3
If a fault has been logged in the ECU:
Action the fault, and carry out an emergency DPF regeneration
4
Inspect the intake and boost system for leaks.
(Including all the hoses and pipe work)
5
Read out the live data for the DPF pressure and temperatures with the ignition on and at idle, the engine must be above 80°C.
DPF pressure should read:
- Ignition on – 0 mbar +/- 1.5 mbar (If outside these specs, then the fault should be a defective pressure sensor or wiring defect)
- Engine idling – 10 mbar +/- 5 mbar (Below would require checking the DPF is intact and over would suggest a partially blocked DPF)
6
Check if all the warning lights for DPF, pre-glow and engine management are on:
a. The soot loading is over 45mg. The vehicle is running in emergency operation.
b. The regeneration cut-off time of 4500 seconds has been exceeded.
c. The soot loading may not be above 45mg to carry out an emergency regeneration.
In either of the above cases, an emergency DPF regeneration would be required.
Note – The engine control module will not allow a regeneration if the soot loading is over 45mg. However, a professional clean and resetting the DPF learnt values may suffice.
7
Inspect other components in the exhaust system before you replace the DPF as it may not be necessary to do this.
Inspection of the following components would be required:
- G450 – Exhaust gas pressure sensor
- G506 / G448 – Temperature sensor before DPF
- G507 / G235 – Temperature sensor before the turbocharger
- G527 – Temperature sensor after the FPF
- G70 – Air mass meter
- G39 – Lambda probe
8
If you cannot find a fault with any of the above exhaust components rectify the DPF fault before you re-assess the soot loading of the DPF through the measuring groups.
