Heated Oxygen Sensor (Front)

FAULT ID
11

TITLE
Heated Oxygen Sensor (front)

BACKGROUND
- The oxygen sensor converts the oxygen density in the exhaust gas to a voltage and outputs it.
- The engine control module checks the change of an oxygen sensor output voltage (Lean/Rich) in the air/fuel ratio closed loop control.

RANGE OF CHECK
- 3 minutes have passed after engine was started.
- Engine coolant temperature is approx. 80°C (176°F) or more.
- Intake air temperature is 20 - 50°C (68 - 122°F).
- Engine speed is approx. 2,000 - 3,000 RPM's
- Vehicle is moving at constant speed on a flat, level road surface.

SET CONDITIONS
The oxygen sensor output voltage does not cross specified voltage for specified seconds.

EFFECT
Limp-in
- Air/fuel ratio closed loop control is not performed.

PROBABLE CAUSES
- Oxygen sensor deteriorated.
- Open or shorted oxygen sensor circuit, or loose connection
- Incorrect fuel pressure.
- Injector failed.
- Air intake.
- Engine control module failed.