P0138

P0138 00

O2S Circuit. High Voltage. Sensor 2.







Fault symptom
- Check Engine

On-board diagnosis

Type of diagnosis:
- Continuous

Enable criteria:
- Battery voltage must be between 11 - 16 V.
- Engine running (with at least 7700 combustions).
- Preheating active for more than 4 s.
- Secondary air pump not active, if fitted.
- EVAP, leak diagnosis inactive (if OBD II).

Fault criteria:
- When voltage across the sensor is more than 1200 mV for 5 s.

Dependent:
- None

System reaction to a fault:
- Preheating is switched off.
- Adaption of rear oxygen sensor is blocked and reset.

OK report:
- Fault criteria NOT fulfilled for 6 s.

Fault handling:
Type III
(See section Fault handling III, "Other emission-related components and functions" for more information.)

Checking the wiring harness
- Move the wiring harness at several spots and in several directions to reveal intermittent breaks and short-circuits. Check switches, connectors and crimp connections for oxidation, retracted pins and pin clamping force.

Diagnostic help

Diagnosis regards:
- Electrical fault in connecting leads or component.

Functions in the diagnostic tool related to the fault:

Test value:
- O2S 2
(See also description of readings/activations in diagnostic tool)