492C

492C - P205B

Information saved in
DDE

Fault code
492C - P205B

Fault text
DDE: Reducing-agent active-tank temperature sensor:

Fault description
A plausibility error at the reduction agent temperature sensor
is recognized when:
Error 1: The tank temperature rises above the limit value -
5 �C and the measured active tank level is less than 9 %.
Or:
Error 2: The tank temperature falls below the limit value -
20 �C and the measured active tank level is greater than 9 %.

Condition for fault identification
Test condition:
For testing of the individual errors the following conditions
must be satisfied:
1.)
- - The calculated tank level is greater than 45 %.
- No other faults have been detected.
2.)
- The outside temperature, the catalyst temperature and the
coolant temperature do not display mutual deviations in
excess of +/- 40 �C.
Voltage condition:
For testing of the individual errors the following conditions
must be satisfied:
1.)
- - The calculated tank level is greater than 45 %.
- No other faults have been detected.
2.)
- The outside temperature, the catalyst temperature and the
coolant temperature do not display mutual deviations in
excess of +/- 40 �C.

Condition for fault memory entry
Debounce (16000 ms)

Action in service
1. Fill active tank.
2. Execute "refill recognition" service function.
3. Use the diagnostic system to read out the tank's contents
and temperature and the data for the transfer pump and then
examine them. Delete the DTC is plausible figures are
indicated.
4. Replace temperature sensor.
5. Replace the transfer-pump assembly.

Fault effect and breakdown warning
-

Driver information
Warning light:
MIL

Service instruction
In winter:
The temperature sensor is defective if a valid level signal is
present at temperatures below -20�C.