Speed sensor TOYOTA RAV4 1996 Service Owner's Manual

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

FI7081
Waveform of oxygen sensor
before catalystNormal
catalystWaveform of oxygen sensor
after catalyst
− DIAGNOSTICSENGINE
DI−73
1996 RAV4 (RM447U)
DTC P0420 Catalyst System Efficiency Below Threshold
CIRCUIT DESCRIPTION
The ECM compares the waveform of the oxygen sensor located before the catalyst with the waveform of
the oxygen sensor located after the catalyst to determine whether or not catalyst performance has deterio-
rated.
Air−fuel ratio feedback compensation keeps the waveform of the oxygen sensor before the catalyst repeat-
edly changing back and forth from rich to lean.
If the catalyst is functioning normally, the waveform of the oxygen sensor after the catalyst switches back
and forth between rich and lean much more slowly than the waveform of the oxygen sensor before the cata-
lyst.
But when both wavaforms change at a similar rate, it indicates that catalyst performance has deteriorated.
DTC NoDTC Detecting ConditionTrouble Area
P0420
After the engine and the catalyst are warmed up, and while the
vehicle is driven within the set vehicle and engine speed range,
the waveforms of the oxygen sensors (bank 1 sensor 1 and
bank 1 sensor 2) have the same amplitude
(2 trip detection logic)
Front TWC (front catalyst) and TWC w/pipe (rear catalyst)
Oxygen sensor
DI3ZV−01

(4) (3)
(2)
(1)
FI7132
2500 − 3000 rpm Engine Speed
Warmed up 3 minutes IG SW OFFIdling
Time
Check
FI6514
OX Signal Waveform (Oscilloscope)
200 msec./Division 1.0 V
0 V DI−74
− DIAGNOSTICSENGINE
1996 RAV4 (RM447U)
CONFIRMATION ENGINE RACING PATTERN
(1) Connect the TOYOTA hand−held tester to the DLC3, or connect the probe of the oscilloscope between
terminals OX1, OX2 and E1 of ECM.
(2) Start engine and warm it up with all accessories switched OFF until water temperature is stable.
(3) Race the engine at 2500 − 3000 rpm for about 3 min.
(4) After confirming that the waveforms of the oxygen sensor, bank 1 sensor 1 (OX1), oscillate around 0.5
V during feedback to the ECM, check the waveform of the oxygen senor, bank 1 sensor 2 (OX2).
HINT:
If there is a malfunction in the system, the waveform of the oxy-
gen senor, bank1 sensor 2 (OX2), is almost the same as that
of the oxygen sensors, bank 1 senor 1 (OX1), on the left.
There are some cases where, even though a malfunction ex-
ists, the MIL may either light up or not light up.

Q00515
4−pulse 4−pluse
ECM Combination
Meter No.1 Vehicle
Speed Sensor
Transaxle DI−94
− DIAGNOSTICSENGINE
1996 RAV4 (RM447U)
DTC P0500 Vehicle Speed Sensor Malfunction
CIRCUIT DESCRIPTION
The No.1 vehicle speed sensor outputs a 4−pulse signal for every revolution of the rotor shaft, which is ro-
tated by the transmission output shaft via the driven gear. After this signal is converted into a more precise
rectangular waveform by the waveform shaping circuit inside the combination meter, it is then transmitted
to the ECM. The ECM determines the vehicle speed based on the frequency of these pulse signals.
DTC No.DTC Detecting ConditionTrouble Area
P0500
No vehicle speed sensor signal to ECM under the following
conditions:
(2 trip detection logic)
For A/T:
(a) Park / neutral position switch is OFF
(b) Vehicle is being driven
For M/T:
(a) Engine speed is between 2,000 rpm and 5,000 rpm
(b) Vehicle is being driven at 88 km/h (54 mph) or more
Open or short in vehicle speed sensor circuit
Vehicle speed sensor
Combination meter
ECM
DI3ZZ−01

A04252
C9V−W
E6ECM
SPD5 V
2
9 Combination Meter
− DIAGNOSTICSENGINE
DI−95
1996 RAV4 (RM447U)
WIRING DIAGRAM
INSPECTION PROCEDURE
1 Check operation of speedometer.
CHECK:
Drive the vehicle and check it the operation of the speedometer in the combination meter is normal.
HINT:
The vehicle speed sensor is operating normally if the speedometer display is normal.
NG Check speedometer circuit. See combination
meter troubleshooting.
OK

DI40C−02
DI−138
− DIAGNOSTICSAUTOMATIC TRANSAXLE (A241E)
1996 RAV4 (RM447U)
DIAGNOSTIC TROUBLE CODE CHART
If a DTC is displayed during the DTC check, check the circuit listed in the table below and proceed to the
page given.
DTC No.
(See page)Detection ItemTrouble AreaMIL*Memory
P0500
(DI−94)Vehicle Speed Sensor
Malfunction
Open or short in vehicle speed sensor circuit
Vehicle speed sensor
Combination meter
ECM

P0750
(DI−146)Shift Solenoid A Malfunction
(Shift Solenoid Valve No. 1)Shift solenoid valve No. 1 is stuck open or closed
Valve body is blocked up or stuck
P0753
(DI−147)Shift Solenoid A Electrical
Malfunction
(Shift Solenoid Valve No. 1)Open or short in shift solenoid valve No. 1 circuit
Shift solenoid valve No. 1
ECM

P0755
(DI−146)Shift Solenoid B Malfunction
(Shift Solenoid Valve No. 2)Shift solenoid valve No. 2 is stuck open or closed
Valve body is blocked up or stuck
P0758
(DI−147)Shift Solenoid ”B” Electrical
Malfunction
(Shift Solenoid Valve No. 2)Open or short in shift solenoid valve No. 2 circuit
Shift solenoid valve No. 2
ECM

P0770
(DI−151)Shift Solenoid E Malfunction
(Shift Solenoid Valve SL)Shift solenoid valve SL is stuck open or closed
Valve body is blocked up or stuck
Lock−up clutch

P0773
(DI−153)Shift Solenoid E Electrical
Malfunction
(Shift Solenoid Valve SL)Open or short in shift solenoid valve SL circuit
Shift solenoid valve SL
ECM

P1780
(DI−156)Park/Neutral Position Switch
MalfunctionShort in park/neutral position switch circuit
Park/neutral position switch
ECM

*:  ...... MIL lights up

DI40G−01
− DIAGNOSTICSAUTOMATIC TRANSAXLE (A241E)
DI−145
1996 RAV4 (RM447U)
CIRCUIT INSPECTION
DTC P0500 Vehicle Speed Sensor Malfunction
See page DI−94.

Q08586
(−) (+)
(−)
(+)
DI−146
− DIAGNOSTICSAUTOMATIC TRANSAXLE (A241E)
1996 RAV4 (RM447U)
DTC P0750, P0755 Shift Solenoid A/B Malfunction
(Shift Solenoid Valve No. 1 / No. 2)
SYSTEM DESCRIPTION
The ECM uses signals from the vehicle speed sensor to detect the actual gear position (1st, 2nd, 3rd or O/D
gear). The ECM then compares the actual gear with the shift schedule in the ECM memory to detect mechan-
ical trouble of the shift solenoid valves and valve body.
DTC No.DTC Detecting ConditionTrouble Area
P0750
P0755During normal driving, the gear required by the ECM does not
match the actual gear (2 trip detection logic)Shift solenoid valve No. 1 / No. 2 is stuck open or closed
Valve body is blocked up or stuck
HINT:
Check the shift solenoid valve No. 1 when DTC P0750 is output and check shift solenoid valve No. 2 when
DTC P0755 is output.
INSPECTION PROCEDURE
1 Check shift solenoid valve No. 1 or No. 2 operation.
PREPARATION:
(a) Remove the oil pan.
(b) Remove the shift solenoid valve No. 1 or No. 2.
CHECK:
(a) Applying 490 kPa (5 kgf/cm2, 71 psi) of compressed air,
check that the shift solenoid valves do not leak air.
(b) When battery positive voltage is supplied to the shift sole-
noid valves, check they open.
NG Replace shift solenoid valve No. 1 or No. 2.
OK
2 Check valve body (See page DI−141).
NG Repair or replace valve body.
OK
Repair transaxle (See page AX−15).
DI40H−01

DI40U−02
− DIAGNOSTICSAUTOMATIC TRANSAXLE (A540H)
DI−189
1996 RAV4 (RM447U)
DIAGNOSTIC TROUBLE CODE CHART
If a DTC is displayed during the DTC check, check the circuit listed in the table below and proceed to the
page given.
DTC No.
(See page)Detection ItemTrouble AreaMIL*Memory
P0500
(DI−94)Vehicle Speed Sensor
Malfunction
Open or short in vehicle speed sensor circuit
Vehicle speed sensor
Combination meter
ECM

P0750
(DI−197)Shift Solenoid A Malfunction
(Shift Solenoid Valve No. 1)Shift solenoid valve No. 1 is stuck open or closed
Valve body is blocked up or stuck
P0753
(DI−198)Shift Solenoid A Electrical
Malfunction
(Shift Solenoid Valve No.1)Open or short in shift solenoid valve No. 1 circuit
Shift solenoid valve No. 1
ECM

P0755
(DI−197)Shift Solenoid B Malfunction
(Shift Solenoid Valve No. 2)Shift solenoid valve No. 2 is stuck open or closed
Valve body is blocked up or stuck
P0758
(DI−198)Shift Solenoid B Electrical
Malfunction
(Shift Solenoid Valve No. 2)Open or short in shift solenoid valve No. 2 circuit
Shift solenoid valve No. 2
ECM

P0770
(DI−201)Shift Solenoid E Malfunction
(Shift Solenoid Valve SL)Shift solenoid valve SL is stuck open or closed
Valve body is blocked up or stuck
Lock−up clutch

P0773
(DI−203)Shift Solenoid E Electrical
Malfunction
(Shift Solenoid Valve SL)Open or short in shift solenoid valve SL circuit
Shift solenoid valve SL
ECM

P1700
(DI−206)Speed sensor No. 2 Circuit
Malfunction
(Front Speed Sensor)Open or short in front speed sensor circuit
Front speed sensor
ECM

P1715
(DI−209)Rear Wheel Sensor Circuit
Malfunction
(Rear Speed Sensor)Open or short in rear speed sensor circuit
Rear speed sensor
ECM

P1760
(DI−212)Linear Solenoid for Line Pres-
sure Control Circuit Malfunction
(Shift Solenoid Valve ST)Open or short in shift solenoid valve ST circuit
Shift solenoid valve ST
ECM

P1770
(DI−215)Differential Lock Solenoid No. 1
Circuit Malfunction
(Shift Solenoid Valve SLD)Open or short in shift solenoid valve SLD circuit
Shift solenoid valve SLD
ECM

P1780
(DI−218)Park/Neutral Position Switch
MalfunctionShort in park/neutral position switch circuit
Park/neutral position switch
ECM

*:  ...... MIL lights up

DI40V−01
D02251
ATF Temperature
SwitchRear Speed Sensor
Shift Solenoid
Valve ST
Park/Neutral
Position Switch
Shift solenoid
Valve No. 1
Shift Solenoid
Valve No .2Shift Solenoid
Valve SLFront Speed SensorShift Solenoid
Valve SLDStop Light Switch O/D OFF Indicator Light O/D Main Switch
Pattern Select
Switch
MIL ECM
DI−190
− DIAGNOSTICSAUTOMATIC TRANSAXLE (A540H)
1996 RAV4 (RM447U)
PARTS LOCATION