Toyota Celica 2005, Repair Manual

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A21566
G and NE Signal Waveforms
G
NE
NE
5 V
/Division
20 msec./Division (Idling)
10 msec./Division (Idling)
G
5 V
/Division
− DIAGNOSTICS ENGINE (2ZZ − GE)
DI − 477
2005 CELICA (RM1131U)
DTC P0335 Crankshaft Position Sensor ”A” Circuit
Malfunction
DTC P0339 Crankshaft Position Sensor ”A” Circuit
Intermittent
CIRCUIT DESCRIPTION
The crankshaft position sensor (NE signal) consists of a magnet, iron core and pickup coil.
The NE signal plate (crankshaft position sensor plate) has 34 teeth and is installed on the crankshaft. The
NE signal sensor generates 34 signals for each engine revolution. This sensor monitors a plate (timing rotor)
located on the crankshaft
timing pulley and is used by the ECM to detect crankshaft angle and engine speed
(RPM/NE). As the crankshaft timing pulley rotates through an engine revolution, this sensor communicates
the rotation of the NE signal plate as a pulse signal to the ECM. Based on the signal, the ECM controls fuel
injection time and ignition timing.
DTC No. DTC Detection Condition Trouble Area
P0335
No crankshaft position sensor signal to ECM during cranking
(2 trip detection logic)
S Open or short in crankshaft position sensor circuit
S Crankshaft position sensor
S Signal plate (crankshaft)
S ECM
No crankshaft position sensor signal to ECM with engine
speed 600 rpm or more (2 trip detection logic)
P0339
In conditions (a), (b) and (c), no crankshaft position sensor
(NE+) signal is input for 0.05 second or more
(a) Engine revolution is 1,000 rpm or more
(b) STA signal is OFF
(c) 3 seconds or more have elapsed after STA signal is
switched from ON to OFF
Reference: Inspection by using the oscilloscope.
HINT:
The correct waveform is as shown on the left.
Item Contents
Terminal
CH1: G+ − NE −
CH2: NE+ − NE −
Equipment Setting 5V/Division, 20ms/Division
Condition During cranking or idling
DIC7H − 02
675