Mazda 2007 CX-9, Особенности сервиса

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CONTROL SYSTEM [MZI-3.5]
01-40–10
HEATED OXYGEN SENSOR (HO2S) FUNCTION [MZI-3.5]
id0140c1178300
•
Detects the oxygen concentration in the exhaust gas.
•
A heater has been adopted to stabilize oxygen concentration detection even when the exhaust gas temperature
is low.
End Of Sie
HEATED OXYGEN SENSOR (HO2S) CONSTRUCTION/OPERATION [MZI-3.5]
id0140c1178400
•
Installed in front of the catalytic converter.
•
The built-in heater promotes activation of the heated oxygen sensor at engine start (when exhaust gas is at low
temperature).
•
A zirconium element is used on the sensor. When
there is a difference between the oxygen
concentration on either side of the element,
electromotive force is generated by the movement
of oxygen ions (atmospheric air on the inner side
of the zirconium element, exhaust gas on the
outer side). The electromotive force changes
significantly at the boundary of the stoichiometric
air/fuel ratio (A/ F=14.7). The PCM inputs the
voltage generated from the HO2S directly, and
increases or decreases the fuel injection amount
by the fuel injection control so that it is close to
the stoichiometric air/fuel ratio.
•
When the temperature of the zirconium element is
low, electromotive force is not generated so the element is heated by a built-in heater, promoting the oxygen
sensor activation. Due to this, the sensor is efficiently activated even immediately after cold-engine start, and a
stable sensor output can be obtained.
End Of Sie
NG: THROTTLE POSITION SENSOR
THROTTLE POSITION (TP) SENSOR FUNCTION [MZI-3.5]
id0140c1178600
•
Detects the throttle valve opening angle.
End Of Sie
THROTTLE POSITION (TP) SENSOR CONSTRUCTION/OPERATION [MZI-3.5]
id0140c1178500
•
The TP sensor is a rotary potentiometer sensor that provides a signal to the PCM that is linearly proportional to
the throttle plate/shaft position.
•
The TP sensor is mounted on the throttle body.
•
As the TP sensor is rotated by the throttle shaft, 4 operating conditions are determined by the PCM from the TP.
The operating conditions
—
Closed throttle (includes idle or deceleration)
—
Part throttle (includes cruise or moderate acceleration)
—
Wide open throttle (includes maximum acceleration or de-choke on crank)
—
Throttle angle rate
End Of Sie
NG: CYLINDER HEAD TEMPERATURE (CHT) SENSOR
CYLINDER HEAD TEMPERATURE (CHT) SENSOR FUNCTION [MZI-3.5]
id0140c1205500
•
Detects the cylinder head temperature.
End Of Sie
14.7
HIGH
OUTPUT
VOLTAGE
LOW
RICH
AIR/FUEL
RATIO
LEAN
atraan00000418
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