2CA9 - P0161

2020 BMW 128i Coupe (E82) L6-3.0L (N51) Diagnostic Trouble Codes ( DTC ): Service instruction

none

2CA9

2CA9 - P0161

Information saved in

DME

Fault code

2CA9 - P0161

Fault text

Oxygen sensor heating behind catalytic converter 2, function

Fault description

O2 Sensor Heater Circuit (Bank 2 Sensor 2)

Condition for fault identification

Test condition:

Check internal resistance of O2 sensor to check sensor heater => If the heater is too weak, the O2 sensor's internal resistance rises too high (= sensor too cold)

No fault memories;

Terminal condition: Terminal 15, engine on Voltage condition:

none

Condition for fault memory entry

Internal resistance R > 12000 Ohm (US) or 15000 Ohm (ECE)

Action in service

Was the temperature drop caused by external factors (driving into snow pile, ice on O2 sensor?) Thaw sensor, clear all fault memory, continue driving!

Check O2 sensor heater: Contact resistance on plugs and in wiring is excessive (DME - wiring harness - sensor)

Check wiring

Check O2 sensor plug (water or corrosion in the plug? Repeatedly disconnect the plug and then re-insert it FIRMLY)

Replace plug and/or wire as indicated

Replace the affected downstream (post-cat) O2 sensor

Fault effect and breakdown warning

Driver information Warning light: MIL ON