1996 TOYOTA RAV4 Sensors

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.

Q08867
Junction Connector
Fuse Block
FL Block
DI−168
− DIAGNOSTICSAUTOMATIC TRANSAXLE (A241E)
1996 RAV4 (RM447U)
Pattern Select Switch Circuit
CIRCUIT DESCRIPTION
The ECM memory contains the shift programs for the NORMAL and POWER patterns, 2 position, and L posi-
tion and the lock−up patterns. Following the programs corresponding to the signals from the pattern select
switch, the park/neutral position switch and other various sensors, the ECM switches the solenoid valves
ON and OFF, and control the transmission gear change and the lock−up clutch operation.
WIRING DIAGRAM
INSPECTION PROCEDURE
1 Check operation of PWR indicator light.
CHECK:
Check if the PWR indicator light normally when the pattern select switch is set to NORM and PWR position.
OK:
Pattern select switchPWR indicator light
PWRLight up
NORMGoes off
NG Check and repair PWR indicator light (See page
BE−2).
OK
DI40P−02

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

Q08867
Junction Connector
Fuse Block
FL Block
− DIAGNOSTICSAUTOMATIC TRANSAXLE (A540H)
DI−229
1996 RAV4 (RM447U)
Pattern Select Switch Circuit
CIRCUIT DESCRIPTION
The ECM memory contains the shift programs for the NORMAL and POWER patterns, 2 and L position and
the lock−up patterns. Following the programs corresponding to the signals from the pattern select switch,
the park / neutral position switch and other various sensors, the ECM switches the solenoid valves ON and
OFF, and control the transmission gear change and the lock−up clutch operation.
WIRING DIAGRAM
INSPECTION PROCEDURE
1 Check operation of PWR indicator light.
CHECK:
Check if the PWR indicator light normally when the pattern select switch is set to NORM and PWR position.
OK:
Pattern select switchPWR indicator light
PWRLight up
NORMGoes off
NG Check and repair PWR indicator light (See page
BE−37).
OK
DI41B−02

N17436CRUISE Indicator Light
DI42I−02
BE4034
ON
OFF1.5 sec 0.5 secWarning
F02201Tc E1
DI−328
− DIAGNOSTICSCRUISE CONTROL SYSTEM
1996 RAV4 (RM447U)
PRE−CHECK
1. DIAGNOSIS SYSTEM
(a) Check the indicator.
(1) Turn the ignition switch to ON.
(2) Check that the CRUISE MAIN indicator light comes
on when the cruise control main switch is pushed
ON, and that the indicator light goes off when the
main switch is pushed OFF.
HINT:
If the indicator check result is not normal, proceed to trouble-
shooting (See page BE−2) for the combination meter
section.
(b) Check the DTC.
HINT:
If a malfunction occurs in the vehicle speed sensors or actuator,
etc. during cruise control driving, the ECU actuates AUTO CAN-
CEL of the cruise control and blinks the CRUISE MAIN indicator
light to inform the driver of a malfunction. At the same time, the
malfunction is stored in memory as a DTC.
(c) Output of DTC using diagnosis check wire.
(1) Turn the ignition switch to ON.
(2) Using SST, connect terminals Tc and E
1 of DLC1.
SST 09843−18020
(3) Read the DTC on the CRUISE MAIN indicator light.
HINT:
If the DTC is not output, inspect the diagnosis circuit (See
page DI−374).
As an example, the blinking patterns for codes; normal,
11 and 21 are shown in the illustration.

N21699
Ignition
Switch
1D 1F1E
1A
1D 1K9
22 4 247
466
B 14
BB
Junction
Connector W−BW−B
13
GND W
IG
Fuse Block
ALT
100 A
BatteryJ/B No.1R/B No.2 J/B No.1
J/B No.1Cruise Control
ECU
Fuse Block
ECU−IG
7.5 AB−Y B−Y
W
B−Y
AM1
40 AW DI−366
− DIAGNOSTICSCRUISE CONTROL SYSTEM
1996 RAV4 (RM447U)
ECU Power Source Circuit
CIRCUIT DESCRIPTION
The ECU power source supplies power to the actuator and sensors, etc., Terminal GND and the cruise con-
trol ECU case are grounded.
WIRING DIAGRAM
DI42X−02

11 5
SRS
NOTICE: When inspecting or repairing the SRS, perform the operation in accordance with the following
precautionary instructions and the procedure and precautions in the Repair Manual for the applicable model
year.

Malfunction symptoms of the supplemental restraint system are difficult to confirm, so the diagnostic trouble
codes become the most important source of information when troubleshooting.
When troubleshooting the supplemental restraint system, always inspect the diagnostic trouble codes before
disconnecting the battery.

Work must be started after 90 seconds from the time the ignition SW is turned to the LOCKº position and the
negative (-) terminal cable is disconnected from the battery.
(The supplemental restraint system is equipped with a back-up power source so that if work is started within
90 seconds of disconnecting the negative (-) terminal cable of the battery, the SRS may be activated.)
When the negative (-) terminal cable is disconnected from the battery, the memory of the clock and audio
systems will be canceled. So before starting work, make a record of the contents memorized by each memory
system. When work is finished, reset the clock and audio system as before and adjust the clock.
To avoid erasing the memory of each memory system, never use a back-up power supply from outside the
vehicle.

When removing the steering wheel pad or handling a new steering wheel pad, keep the pad upper surface
facing upward. Also, lock the lock lever of the twin lock type connector at the rear of the pad and take care
not to damage the connector.
(Storing the pad with its metallic surface up may lead to a serious accident if the SRS inflates for some reason.)

Always store a removed or new front passenger airbag assembly with the airbag door facing up. Storing the
airbag assembly with the airbag door facing down could cause a serious accident if the airbag inflates.

Store the steering wheel pad where the ambient temperature remains below 935C (2005F), without high
humidity and away from electrical noise.

Never use SRS parts from another vehicle. When replacing parts, replace them with new parts.

Never disassemble and repair the steering wheel pad, front passenger airbag assembly, airbag sensor
assembly.

Before repairing the body, remove the airbag sensor if during repair shocks are likely to be applied to the
sensors due to vibration of the body or direct tapping with tools or other parts.

Do not reuse a steering wheel pad or front airbag sensors.
After evaluating whether the center airbag sensor assembly is damaged or not, decide whether or not to reuse
it. (See the Repair Manual for the method for evaluating the center airbag sensor assembly.)

When troubleshooting the supplemental restraint system, use a high-impedance (Min. 10kW/V) tester.

The wire harness of the supplemental restraint system is integrated with the instrument panel wire harness
assembly.
The vehicle wiring harness exclusively for the airbag system is distinguished by corrugated yellow tubing, as
are the connectors.

Do not measure the resistance of the airbag squibs.
(It is possible this will deploy the airbag and is very dangerous.)

If the wire harness used in the supplemental restraint system is damaged, replace the whole wire harness
assembly.

INFORMATION LABELS (NOTICES) are attached to the periphery of the SRS components. Follow the
instructions on the notices.