Sensor TOYOTA RAV4 1996 Service Workshop Manual

P19750
Knock Sensor 1
E1 KNKECM
10
E5 B
1 DI−56
− DIAGNOSTICSENGINE
1996 RAV4 (RM447U)
DTC P0325 Knock Sensor 1 Circuit Malfunction
CIRCUIT DESCRIPTION
A knock sensor is fitted to the cylinder block to detect engine knocking. This sensor contains a piezoelectric
element which generates a voltage when it becomes deformed, which occurs when the cylinder block vi-
brates due to knocking. If engine knocking occurs, ignition timing is retarded to suppress it.
DTC No.DTC Detecting ConditionTrouble Area
P0325No knock sensor 1 signal to ECM with engine speed 1,200 rpm
or more (2 trip detection logic)Open or short in knock sensor 1 circuit
Knock sensor 1 (looseness)
ECM
If the ECM detects the above diagnosis conditions, it operates the fail safe function in which the corrective
retard angle value is set to the maximum value.
WIRING DIAGRAM
DI3ZP−01

BE6053S02469A07399
LOCK
E5 ConnectorKNK
(+)
− DIAGNOSTICSENGINE
DI−57
1996 RAV4 (RM447U)
INSPECTION PROCEDURE
1 Check continuity between terminal KNK of ECM connector and body ground.
PREPARATION:
(a) Remove side trim cover (See page SF−61).
(b) Disconnect the E5 connector of ECM.
CHECK:
Measure resistance between terminal KNK of ECM connector
and body ground.
OK:
Resistance: 1M Ω or higher
OK Go to step 3.
NG
2 Check knock sensor (See page SF−57).
NG Repair knock sensor.
OK
3 Check for open and short in harness and connector between ECM and knock
sensor (See page IN−30).
NG Repair or replace harness or connector.
OK
4 Does malfunction disappear when a good knock sensor is installed?
YES Replace knock sensor.
NO

A00406
0.5 V/
Division
0.5 V/
Division5 m sec./Division Knock signal waveform
0 V
0 V
100 μ sec./Division DI−58
− DIAGNOSTICSENGINE
1996 RAV4 (RM447U)
Check and replace ECM (See page IN−30).
Reference INSPECTION USING OSCILLOSCOPE
With the engine racing (4,000 rpm) measure between ter-
minal KNK of ECM and body ground.
HINT:
The correct waveform is as shown.
Spread the time on the horizontal axis, and confirm that
period of the wave is 132
sec.
(Normal mode vibration frequency of knock sensor: 7.6
KHz).
HINT:
If normal mode vibration frequency is not 7.6 KHz, the sensor
is malfunctioning.

S02414
Distributor
Camshaft Position Sensor
(Built into Distributor)
D16
D16E4
E4
E4 1
B
R
W
G 1
2G4 5
17NE 
NE 
E1 ECM
Crankshaft Position Sensor2G 
W
− DIAGNOSTICSENGINE
DI−59
1996 RAV4 (RM447U)
DTC P0335 Crankshaft Position Sensor ”A” Circuit
Malfunction
CIRCUIT DESCRIPTION
Crankshaft position sensor (NE signal) consists of a signal plate and pickup coil.
The NE signal plate has 34 teeth and is mounted on the crankshaft. The NE signal sensor generates 34
signals for every engine revolution. The ECM detects the standard crankshaft angle based on the G signals,
and the actual crankshaft angle and the engine speed by the NE signals.
DTC No.DTC Detecting ConditionTrouble Area
P0335
No crankshaft position sensor signal to ECM during cranking
(2 trip detection logic)Open or short in crankshaft position sensor circuit
Crankshaft position sensor
Starter
ECM
No crankshaft position sensor signal to ECM with engine
speed 600 rpm or more
(2 trip detection logic)
WIRING DIAGRAM
DI3ZQ−01

FI7059FI7060A06620
NENEG
G20 m sec./Division (Idling)
10 m sec./Division (Idling)
5 V/Division
5 V/Division
DI−60
− DIAGNOSTICSENGINE
1996 RAV4 (RM447U)
INSPECTION PROCEDURE
1 Check resistance of crankshaft position sensor (See page IG−14).
Reference:
INSPECTION USING OSCILLOSCOPE
During cranking or idling, check between terminals G  and NE
, NE  and NE  of ECM.
HINT:
The correct waveforms are as shown.
NG Replace crankshaft position sensor.
OK
2 Check for open and short in harness and connector between ECM and crank-
shaft position sensor (See page IN−30).
NG Repair or replace harness or connector.
OK

− DIAGNOSTICSENGINE
DI−61
1996 RAV4 (RM447U)
3 Inspect sensor installation and teeth of signal plate.
NG Tighten the sensor.
Replace signal plate.
OK
Check and replace ECM (See page IN−30).

DI−62
− DIAGNOSTICSENGINE
1996 RAV4 (RM447U)
DTC P0336 Crankshaft Position Sensor Circuit Range /
Performance
CIRCUIT DESCRIPTION
Refer to Crankshaft Position Sensor ”A” Circuit Malfunction on page DI−59.
DTC No.DTC Detecting ConditionTrouble Area
P0336Engine control computer malfunction (for backup)Distributor
ECM
WIRING DIAGRAM
Refer to page DI−59.
INSPECTION PROCEDURE
1 Are there any other codes (besides DTC P0336) being output?
YES Go to relevant DTC chart.
NO
Check and replace ECM
(See page IN−30).
DI3ZR−01

− DIAGNOSTICSENGINE
DI−63
1996 RAV4 (RM447U)
DTC P0340 Camshaft Position Sensor Circuit
Malfunction
CIRCUIT DESCRIPTION
Camshaft position sensor (G signal) consist of a signal plate an pickup coil.
The G signal plate has one tooth on its outer circumference and is built into the distributor.
When the camshaft rotate, the protrusion on the signal plate and the air gap on the pickup coil change, caus-
ing fluctuations in the magnetic field and generating an electromotive force in the pickup coil.
The NE signal plate has 34 teeth and is mounted on the crankshaft. The NE signal sensor generates 34
signals for every engine revolution. The ECM detects the standard crankshaft angle based on the G signal
and the actual crankshaft angle and the engine speed by the NE signals.
DTC No.Detection ConditionTrouble Area
P0340No camshaft position sensor signal to ECM with engine speed
600 rpm or more
Open or short in camshaft position sensor circuit
Camshaft position sensor
Starter
ECM
WIRING DIAGRAM
Refer to page DI−59 for the WIRING DIAGRAM.
INSPECTION PROCEDURE
1 Check resistance of camshaft position sensor (signal generator) (See page
IG−14).
Reference:
INSPECTION USING OSCILLOSCOPE
Refer to page DI−59 for the OSCILLOSCOPE.
NG Replace camshaft position sensor.
OK
2 Check for open and short in harness and connector between ECM and camshaft
position sensor (See page IN−30).
NG Repair or replace harness or connector.
OK
DI3ZS−01

DI−64
− DIAGNOSTICSENGINE
1996 RAV4 (RM447U)
3 Inspect sensor installation.
NG Tighten the sensor.
OK
Check and replace ECM (See page IN−30).

P25430
Throttle Body
Exhaust GasEGR Valve
Diagram ECM
VSV
Throttle
Valve
Intake Air
Chamber
EGR
Vacuum
Modulator
S02387
From
Battery6
1J2
1
1E J/B No.1EFI Main Relay
Fuse Block
11
10E423
EA12 R/B No.6ECM
J1
Junction Connector
AA
W−B B−W VSV (for EGR)
2
1
B−O
IGNEGR
E01
EAFrom
IG Switch
B−O 666 3
125
R−W
B−RB−R
W−B
− DIAGNOSTICSENGINE
DI−65
1996 RAV4 (RM447U)
DTC P0401 Exhaust Gas Recirculation Flow Insufficient
Detected
CIRCUIT DESCRIPTION
The EGR system recirculates exhaust gas, which is controlled to the proper quantity to suit the driving condi-
tions, into the intake air mixture to slow down combustion, reduce the combustion temperature and reduce
NOx emissions. The amount of EGR is regulated by the EGR vacuum modulator according to the engine
load.
If even one the following conditions is fulfilled, the VSV is turned
ON by a signal from ECM. This results in atmospheric air acting
on the EGR valve, closing the EGR valve and shutting off the
exhaust gas (EGR cut−off).
Before the engine is warmed up
During deceleration (throttle valve closed) .
Light engine load (amount of intake air very small).
Engine idling.
Engine speed over 4,400 rpm.
High engine load (amount of intake air very large)
.
DTC No.DTC Detecting ConditionTrouble Area
P0401
After the engine is warmed up, the intake manifold absolute
pressure is lager than the valve calculated by the ECM while
the EGR system is ON
(2 trip detected logic)
EGR valve stuck closed
Open or short in VSV circuit for EGR
Vacuum or EGR hose disconnected
Manifold absolute pressure sensor
EGR VSV open or close malfunction
ECM
WIRING DIAGRAM
DI3ZT−01