Suzuki 2006 SX4, Руководство по обслуживанию

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1A-12 Engine General Information and Diagnosis:
Description of Electric Throttle Body System Calibration
S6RW0C1101018
ECM calculates controlled opening of the throttle valve on the basis of the completely closed throttle valve position of
the electric throttle body system. The completely closed position data is saved in memory of ECM. However, the
completely closed position of the throttle valve of the electric throttle body system (signal voltage from TP sensor when
throttle is completely closed) differs one from the other depending on individual differences of the throttle valve and TP
sensor. As such individual differences must be taken into account for controlling the throttle valve, it is necessary to
register the completely closed throttle valve position data in ECM. When such data is registered in ECM, it is saved in
RAM (memory) of ECM and used as the base data for controlling the throttle valve. This data is cleared, when any of
the works described in “Precautions of Electric Throttle Body System Calibration” is performed.
Also, after replacement of the throttle body and/or APP sensor assembly, the completely closed position data in
memory of ECM must be cleared once and a new one must be registered, or ECM cannot judge the complete closure
position properly.
For the procedure to register such data, refer to “Electric Throttle Body System Calibration in Section 1C”. (After the
completely closed position data is cleared, ECM, for the first time only, opens and closes the throttle valve for about 5
sec. after the ignition switch is turned ON position, for registration of the completely closed throttle valve position. If the
engine is started during this registration process, such symptom as “longer cranking time” or “slow rise of revolution
speed immediately after start-up” may occur. However, turning OFF the ignition switch once and restarting will set
correct registration.)
A/F Sensor Description
S6RW0C1101020
A/F sensor (1), in place of the conventional HO2S-1, is installed in the center of the exhaust manifold joining section
and it consists of a zirconia element (2) which causes the output current to vary according to difference in the oxygen
concentration and a heater (3) which activates the element.
A/F sensor detects oxygen concentration in exhaust gas (9) (A/F ratio of the air-fuel mixture) linearly, ranging from
LEAN to RICH.
Operation
ECM (5) controls the sensor heater (3) and keeps the sensor element temperature at the specified level (about 750
°
C) constantly so that the A/F sensor is activated in the specified way for accurate A/F detection. When the sensor
element reaches the specified temperature (it is activated), its impedance drops to the specified value (approx. 30
Ω
)
by its characteristic.
When a certain voltage (about 0.4 V) is applied between sensor elements in this state, circuit current corresponding to
the sensor element impedance flows in the sensor circuit. ECM detects this circuit current and judges whether the
sensor is in the active state or not. At this time, sensor current is output linearly in the range of +0.01 mA to +some mA
on the lean side and –0.01 mA to – some mA on the rich side. The variation in these ranges depends on the difference
from the stoichiometry A/F ratio, that is, the amount of oxygen between the atmosphere side (6) and exhaust manifold
(7).
According to this sensor output, ECM executes A/F feedback (fuel trim) to achieve the target A/F ratio.