HO2S HEATER CONTROL OPERATION [LF, L3]

id0140a6103400

Front

Operation condition

• The PCM operates the front HO2S heater according to engine operation conditions as shown in the table below.

Drive duty ratio

Engine operation conditions

20 %

• Engine coolant temperature 5 °C {41 °F} or less

35 %

• At engine start
• During engine rotation except idling
• When a DTC indicating a damaged engine coolant temperature sensor, throttle position sensor or intake air temperature sensor is detected.

100 %

• For a fixed period of time after engine start when the engine coolant temperature at engine start is 50 °C {122 °F} or less than the engine coolant temperature when the engine is stopped from a previous operation (differs from engine coolant temperature at engine start [lower engine coolant temperature→longer time])

Inhibition conditions

• When all of the following conditions are met (for 6 s):
- During torque reduction execution
- Engine speed is 5,000 rpm or more.
- Throttle opening angle 85 % or more
• Engine speed 4,000 rpm or more
• During high load
• When HO2S is damaged
• When ignition switch is turned to the ON position while engine is stopped

Rear

Operation conditions

• When all of the following conditions are met:
- After fixed period of time from engine start
- Engine speed is less than 4,000 rpm.
- Except during torque reduction execution
- During low load