277D - P2099 (DME)
277D - P2099Information saved in
DME
Fault code
277D - P2099
Fault text
Oxygen sensor trim control diagnosis, Bank 2
Fault description
Condition for fault identification
Test condition:
Active trim control (steady-state operation between 2000
and 3000 1 rpm in part-load range....min. 120 sec.) and I-
component determination must have taken place
Terminal condition: Engine running
Voltage condition:
none
Condition for fault memory entry
Suspicion of lean condition based on consideration of I-
component (K_LA_TRIM_DIAG_I_Min_SCHW
recognition of I-component limits) leads to a targeted
rich/lean control intervention;
if the pre-cat and post-catalyst oxygen sensors respond as
expected, then a trim control error is recognized.
Action in service
1) Check induction system and exhaust system for leaks;
incl. operation of the HFM/ ...if no defect is present. 2.)
Carry out oxygen sensor test routine. 3.) If the system test
fails to produce a result and the trim control error is still
present -> Replace the pre-catalyst oxygen sensor.
Fault effect and breakdown warning
MIL on after engine runs 2x / no effects on drivability
Driver information
Warning light:
No
Service instruction
none