2019 BMW 128i Convertible (E88) L6-3.0L (N51) A L L Diagnostic Trouble Codes ( DTC ): Manufacturer Code Charts Page 134
Oxygen sensor before catalytic converter, line fault
Fault description
O2 Sensor Pumping Current Trim Circuit/Open (Bank 1
Sensor 1)
Condition for fault identification
Test condition:
O2 sensor wire monitoring
Voltage of O2 sensor signal is too high during overrun cutoff
phase.
overrun injection deactivation
Terminal condition: Terminal 15, engine on
Voltage condition:
none
Condition for fault memory entry
Voltage >5.8 V during overrun injection deactivation
Action in service
1. Visual inspection of wires, DME plug and O2 sensor for
damage
2. Inspect wires
3. Check plug-in connections DME <=> Wiring harness
<=> Upstream (pre-cat) O2 sensor for Bank 1 (water or
corrosion in plug?) => Repeatedly remove the plug and then
reconnect it FIRMLY)
4. Check catalytic converter (is FSD lean fault entered for
the other bank?)
5. Piston rings, injectors, positive crankcase ventilation OK?
FSD fault? Then continue there!
6. Replace O2 sensor
7. Replace DME
Fault effect and breakdown warning
Driver information
Warning light:
MIL ON
Service instruction
none
(DME) Condition For Fault Memory Entry - None
2C3D - P112C
Information saved in
DME
Fault code
2C3D - P112C
Fault text
Oxygen sensor before catalytic converter, line fault
Fault description
O2 Sensor Negative Current or Positive Current Control
Circuit/Open (Bank 1 Sensor 1)
Condition for fault identification
Test condition:
Not supported
Terminal condition: none
Voltage condition:
none
Condition for fault memory entry
