128F04 - P112D (DME)

128F04 - P112D

Information saved in
DME

Fault code
128F04 - P112D

Fault text
Oxygen sensor before catalytic converter 2, line fault: Open
circuit, virtual earth or pump power supply line

Fault description
The diagnostic function monitors sensor voltage, including
in overrun phases.

Condition for fault identification
Test condition:
The fault is recognized when the sensor voltage is higher
than 1.899 V and less than 2.1 V or less than 2.1 V in
overrun mode.
Potential problem source(s):
- Defect in wiring harness to pre-catalyst oxygen sensor 2
- Oxygen sensor 2 forward of catalytic converter defective
- Defective DME
- Defective catalytic converter (rich exhaust gas in overrun
caused by oil or fuel in exhaust)
Terminal condition: none
Voltage condition:
- None
Temperature condition:
- Engine temperature > 85 °C
Time condition:
- None
Other conditions:
- Engine on

Condition for fault memory entry
The diagnostic fault code is logged when the condition
remains present for over 9 seconds during overrun
operation.

Action in service
- Defect in wiring harness to pre-catalyst oxygen sensor 2
- Replace pre-catalyst oxygen sensor 2
- Replace DME

Fault effect and breakdown warning
Breakdown notice:
- none
Possible apparent symptoms:
- none

Driver information
Warning light:
- ECE emissions warning lamp: on
- US emissions warning lamp: on
- ECE electronic engine power reduction: off
- US electronic engine power reduction: off
- CC message: none

Service instruction
none