P22A7

4926 - P22A7

Information saved in
DDE

Fault code
4926 - P22A7

Fault text
DDE: Nitrogen oxide sensor downstream of SCR catalytic
converter:

Fault description
Monitoring NOx signal ready status of NOx sensor behind
SCR converter.
The diagnostic trouble code is logged when the NOx sensor
is ready and does not transmit any valid NOx status
information for at least 10000 ms.

Condition for fault identification
Test condition:
The error is evaluated just once at the start of the driving
cycle after the dew point has been reached and while the
NOx sensor heater diagnosis is activated.
Voltage condition:
The error is evaluated just once at the start of the driving
cycle after the dew point has been reached and while the
NOx sensor heater diagnosis is activated.

Condition for fault memory entry
Event debounced (2)

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

Fault effect and breakdown warning
-

Driver information
Warning light:
MIL

Service instruction
none