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P1142

Read the instructions below then start the fault diagnostic procedure.

Symptom: CHECK ENGINE.

P1142


O2S Heater Circuit. Current too High, Sensor 2.


Fault symptoms


CHECK ENGINE.


On-Board Diagnostics

Type of diagnosis:


- Continuous. But interrupted when fault criteria fulfilled and will not restart until next driving cycle.


Enable criteria:


- General conditions for this trouble code: When starting the engine, the atmospheric pressure must exceed 78 kPa and the engine coolant and intake air temperatures must exceed -7°C.

- Test 1: Engine running. Main relay voltage exceeding 10V. Pre-heating active.

- Test 2: Engine running. Main relay voltage exceeding 10V. Pre-heating active for more than 60 s.


Fault criteria:


- Test 1: Output voltage exceeding 2V for more than 5 s.

- Test 2: Current exceeding 2300 mA for more than 5 s.


Dependents:


- None.


System reaction to a fault:


- Oxygen sensor affect on closed loop is zeroed.


OK report:


- Enable criteria fulfilled. Fault criteria for P1141 or P1142 not fulfilled within 60 s.


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


- Type III.


Diagnostic help

Fault diagnosis concerns an electrical fault in connecting leads or in the sensor.

Functions in the diagnostic tool related to the fault:


Diagnostic status for the diagnosis.

Activate output for pre-heating.

Oxygen sensor pre-heating current, unit mA.


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.

See also description on activating under "Activate" menu for more information.