Toyota Celica 2005, Руководство по ремонту

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− DIAGNOSTICS ENGINE (1ZZ − FE)
DI − 175
2005 CELICA (RM1131U)
MONITOR DESCRIPTION
The knock sensor located on the cylinder block, detects spark knock.
When spark knock occurs, the sensor pick
− up vibrates in a specific frequency range. When the ECM detects
the voltage in this frequency range, it retards the ignition timing to suppress the spark knock.
The ECM also senses background engine noise with the knock sensor and uses this noise to check for faults
in the sensor. If the knock sensor signal level is too low for more than 10 sec., and if the knock sensor output
voltage is out of normal range,the ECM interprets this as a fault in the knock sensor and sets a DTC.
MONITOR STRATEGY
Related DTCs P0325 Knock sensor (Bank 1) range check or rationality
Required sensors/components
Main sensors/components Knock sensor
Related sensors/components
Crankshaft position sensor, Camshaft position
sensor, Engine coolant temperature sensor,
Mass air flow meter
Frequency of operation Continuous
Duration 10 sec.
MIL operation Immediate
Sequence of operation None
TYPICAL ENABLING CONDITIONS
Item
Specification
Minimum Maximum
The monitor will run whenever this DTC is
not present
See page DI − 3
Battery voltage 10 V −
Idle OFF
Time after engine start 5 sec. −
Engine coolant temperature 60
_
C (140
_
F) −
Intake air amount per revolution 0.3 g/rev −
TYPICAL MALFUNCTION THRESHOLDS
Detection Criteria Threshold
Sensor failure is indicated when the knock sensor output
level is below the specific threshold for:
10 sec.
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