Defreezing mode error in the EEC system
Check that the coolant water level not is to low.To verify that the pressure line heater is working, start the engine and check that the pressure line gets warm. If not, check the pressure line for bends, leakage or blockage of the water path. Also check that the water valve opens fully.If the heater is working, dismount and clean the nozzle, steel pipe or dosing unit.For engines with NOx-control software, confirmation of repair requires:- Urea box temperature is greater than -8 degC- Urea tank temperature is greater than -8 degC- Urea temperature in dosing module is greater than -8 degC- Execute the ‘SCR invalidation test’ with SDP3 (takes approximately 30 minutes and needs to be run outdoors)- Or make sure the urea gets defrozen and catalyst temperature is raised to 130 degCIf the fault is remedied, the DTC should now be passive.
What you'll see
No driver-visible symptom recorded.
System reaction
The EEC system will not inject any urea, which leads to higher emissions.For engines with NOx-control software, this DTC is classed as a type D failure.
Diagnostic depth
Defreezing of pressure line has failed 14 times, i.e. the urea pressure is still above 2.0 bar after opening the dosing valve for 360 seconds.(Refer BOSCH SW-specification Y281S01334-VC0 for more details. Error path: ep04_s_def_ouw.9, hhsm_s_def_ouc.1.)
The defreezing mode error might be caused by: - Frozen urea in the pressure line.- Frozen urea or urea crystals in the dosing unit.- Frozen urea or urea crystals in the steel pipe.- Frozen urea or urea crystals in the nozzle.