Manufacturer Code Charts: 4955

4955 - P229F

Information saved in
DDE

Fault code
4955 - P229F

Fault text
NOx sensor after SCR catalytic converter, NOx plausibility:
Required nitrogen oxide signal change not plausible for
nitrogen oxide signal before SCR catalytic converter during
load reversal

Fault description
Plausibility check on NOx sensor behind SCR converter.
The system waits for NOx peaks of an adequate intensity
before the SCR converter for plausibility check on the NOx
sensor behind the SCR converter.
If the sensor's shift in NOx concentration fails to reach the
limit value for the operating point the diagnostic trouble
code is logged.

Condition for fault identification
Test condition:
-
Voltage condition:
-

Condition for fault memory entry
Event debounced (1)

Action in service
1. Check wires and plug connections.
2. If wiring and plug connections are OK:
Replace NOx sensor behind SCR converter.

Fault effect and breakdown warning
-

Driver information
Warning light:
MIL

Service instruction
none