46A4 - P229F (DDE)

46A4 - P229F

Information saved in
DDE

Fault code
46A4 - P229F

Fault text
DDE: NOx sensor after DeNOx cat., plausibility NOx: NOx
signal offset too high at trailing throttle

Fault description
Monitoring of NOx signal offset value (NOx sensor 2
behind SCR). The diagnostic trouble code is logged when
the average offset value exceeds the limit of 30 ppm. The
offset is calculated by averaging the pressure-compensated
signal with the constant 1.

Condition for fault identification
Test condition:
The test routine is executed when the signal flank rises for a
duration of Exh_tiNOxOfsTstVldNoCat2Ds. Within this
time frame the absolute difference between the maximum
and minimum NOx value must be less than 2 ppm. Once the
diagnostic function is enabled the test routine is executed
continuously in accordance with the defined process grid.
Voltage condition:
The test routine is executed when the signal flank rises for a
duration of Exh_tiNOxOfsTstVldNoCat2Ds. Within this
time frame the absolute difference between the maximum
and minimum NOx value must be less than 2 ppm. Once the
diagnostic function is enabled the test routine is executed
continuously in accordance with the defined process grid.

Condition for fault memory entry
Event debounced (1)

Action in service
Use SCR converter system check to analyse NOx sensor 2
(behind SCR converter).
ID0004
ID0005
3. Replace NOx sensor 2 (behind SCR converter).

Fault effect and breakdown warning
Proceed to the nearest BMW Service facility.

Driver information
Warning light:
MIL

Service instruction
Perform metering diagnosis if indicated.