2B98

2B98 - P3247

Information saved in
DME

Fault code
2B98 - P3247

Fault text
DME2: Control unit, bank 2, internal fault: RAM backup,
plausibility

Fault description
Control module, internal fault: RAM backup plausibility

Condition for fault identification
Test condition:
Following recognized HW power failure and successful
download of NVRAM backup (B_restore=true &
B_restoreok=true) as well as successful EEPROM readout
check on currency is performed in the ERCOSEK-INI task
through comparison of counters eepnvrbctr
and nvrbactctr with generation of differential.
If the difference (dnvrbupctr = eepnvrbctr - nvrbactctr)
exceeds a threshold defined in the application (DNVRBUP=
1), the task
_FcmClr (delete stored DTCs) is requested (sequence
control: fcmstate=1) and executed in wake-up. Following
completion of DTC deletion in
ECU error memory (sequence control: fcmstate=2) the DTC
"NVRAM backup not current" is entered in the _100 ms
process. Because the error criterion can only be checked
following a HW power failure with subsequent readback of
the NVRAM backup no error debounce is possible with
driving cycles. The entire error memory log is deleted before
the DTC is entered again in any case.
Terminal condition: Terminal 15=TRUE
Voltage condition:
9.5 < U < 17.9

Condition for fault memory entry
none

Action in service
Check CAN network, replace battery as indicated

Fault effect and breakdown warning
none

Driver information
Warning light:
none

Service instruction
none