Urea pressure in the EEC system
Check if the vent valve is stuck open.Check the urea pipes for leakage.
What you'll see
No driver-visible symptom recorded.
System reaction
The EEC system will be shut off until next driving cycle (ignition key off) and will not inject any urea, which leads to higher emissions. Fault code 100C, 100A and 100B (CAN time out) may occur when the system is shut off. Always trouble shoot this fault code before considering 100C, 100A or 100B.NOTE: The diagnosis for this fault code can not be performed when the EEC system is shut off. Thus the fault code can not become passive or be regenerated (if erased) until next driving cycle. Switch off ignition key for 90 seconds and switch it on again before reading fault codes.
Diagnostic depth
The urea pressure decreases more than 0.5 bar during startup. (Refer BOSCH SW-specification Y281S01334-VC0 for more details. Error path: ep08_s_def_ouw.8, slks_s_def_ouc.5.)
Leakage in the urea path or vent valve stuck open.