Fault Conditions

P0140

O2S Circuit. No Activity Detected. Sensor 2.







Fault symptoms
- CHECK ENGINE.
- Possible misfiring before DTC is generated.

On-Board Diagnostics Type of diagnosis:
- Once per driving cycle. Interrupted when fault criteria fulfilled or OK reported. Restarts next driving cycle.

Enable criteria:
- General conditions for this trouble code: Atmospheric pressure must exceed 72 kPa and the engine coolant and intake air temperature must exceed 7 °C.
- Engine running. Closed loop active. Coolant temperature above 70 °C. Sensor preheating active. Vehicle speed above 0. A counter accumulates the time during which all the conditions are fulfilled. Another counter accumulates changes in sensor voltage.

Fault criteria:
- Accumulated voltage transitions less than 500 mV when time counter reaches 500 s.

Dependents:
- P0116, P0117, P0118, P0501, P0502, P1141 and P1142.

System reaction to a fault:
- Transition adaptation of closed loop is blocked.

OK report:
- P0140 diagnosis performed once and fault criteria not fulfilled. Fault criteria for P0138 not fulfilled.

Fault handling: (See "Fault diagnosis, general" for more information.) Initial Inspection and Diagnostic Overview
- Type III.

Diagnostic help
Fault diagnosis concerns electrical faults in connected leads or in the sensor.

Diagnostic tool functions related to this fault are:
- Diagnostic status for the diagnosis.
- Heated oxygen sensor reading, in V.

See also the description of test values under "Fault diagnosis, general" for more information. Initial Inspection and Diagnostic Overview


NOTE: Oxygen sensor receives references oxygen from the surrounding air via the connecting cables. For this reason, electrical contact spray or grease must not have used on the oxygen sensor connector.


Checking the wiring
Jiggle the wiring harness at several points and in different directions to detect intermittent breaks and short circuits. Observe the multimeter, diagnostic tool or test lamp during the check.