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G643(E) Service Manual
Chapter 5. Engine Management System (EMS)
185
Circuit Diagram (G643)
Sensor Inspection
1.
Using a multimeter, measure the IAT sensor
resistance between terminals 3 and 4.
Temperature
℃
(
°
F)
Resistance(k
Ω
)
0 (32)
4.5 ~ 7.5
20 (68)
2.0 ~ 3.0
40 (104)
0.7 ~ 1.6
IG.SW.ON
80 (176)
0.2 ~ 0.4
2.
If the resistance deviates from the standard value,
replace the intake air temperature sensor
assembly.
OxygenSensor (Pre-Catalyst) [G643E]
Component Location
Pre - Catalyst Oxygen Sensor
Description
The heated oxygen sensor is mounted on the front
side of Catalytic Muffler, which detects the oxygen
concentration in the exhaust gas. The heated
oxygen sensor produces a voltage that varies
between 0V and 1V. When the air/fuel ratio is lean,
the oxygen concentration in the exhaust gas
increases and the front HO2S outputs a low voltage
(approximately0~0.1V). When the air/fuel ratio is
rich, the oxygen concentration in the exhaust gas
decreases and the front HO2S outputs a high
voltage (approximately0.8~1V). The ECM constantly
monitors the HO2S and increases or decreases the
fuel injection duration by using the HO2S signal,
which is called closed-loop fuel control operation.
Specification
Temperature
Temperature
(
℃
)
(
℉
)
Front
HO2S
Heater
Resis-
tance(
Ω
)
(
℃
) (
℉
)
Front HO2S
Heater
Resistance
(
Ω
)
20 68 9.2 400
752 17.7
100
212
10.7 500 932 19.2
200
392
13.1 600
1,112 20.7
300
572
14.6 700
1,292 22.5
Содержание G643
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Страница 43: ...G643 E Service Manual Chapter 3 Engine Mechanical System 41 Engine Exploded View...
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Страница 132: ...G643 E Service Manual Chapter 4 Engine Electrical System 130 2 Alternator and outer terminal connection inspection...
Страница 181: ...G643 E Service Manual Chapter 5 Engine Management System EMS 179 SECM Wiring Diagrams for G643 LP Engine...
Страница 182: ...G643 E Service Manual Chapter 5 Engine Management System EMS 180...
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