egr TOYOTA RAV4 1996 Service Repair Manual

N11771
1
82 3
4
65 7
BE0J4−04
Z10028
1
2
OFF
ON
N01923
N01924
N01925
− BODY ELECTRICALIGNITION SWITCH AND KEY UNLOCK WARNING
SWITCHBE−11
1996 RAV4 (RM447U)
INSPECTION
1. INSPECT IGNITION SWITCH CONTINUITY
Switch positionTester connectionSpecified condition
LOCK−No continuity
ACC2 − 3Continuity
ON2 − 3 − 4, 6 − 7Continuity
START1−2−4, 6−7−8Continuity
If continuity is not as specified, replace the switch.
2. INSPECT KEY UNLOCK WARNING SWITCH CONTI-
NUITY
Switch positionTester connectionSpecified condition
SW OFF
(Key removed) −No continuity
SW ON (Key set)1 − 2Continuity
If continuity is not as specified, replace the switch.
3. Key Unlock Warning System:
INSPECT INTEGRATION RELAY OPERATION
(a) Connect the positive (+) lead from the battery to terminal
A1.
(b) Connect the negative (−) lead from the battery to termi-
nals A5, A6 and A10.
(c) Check the buzzer sounds.
(d) Disconnect the negative (−) lead from the battery to termi-
nals A6.
(e) Check that the buzzer stops sounding.
(f) Connect the negative (−) lead from the battery to termi-
nals A6.
(g) Disconnect the negative (−) lead from the battery to termi-
nals A5.
(h) Check that the buzzer stops sounding.
If operation is not as specified, replace the relay.

BE−12− BODY ELECTRICALIGNITION SWITCH AND KEY UNLOCK WARNING
SWITCH
1996 RAV4 (RM447U)
4. INSPECT INTEGRATION RELAY CIRCUIT (See page
BE−37)
5. INSPECT DOOR COURTESY SWITCH CONTINUITY
(See Page BE−22)

BE1MW−01
Z17623
HEAD
TA I L
OFFRight
LeftFlash
8
7
17 16
1413
Z13558
3
4
21
3
4 2
1
Z05657
3 21 3
21
55
− BODY ELECTRICALHEADLIGHT AND TAILLIGHT SYSTEM
BE−15
1996 RAV4 (RM447U)
INSPECTION
1. INSPECT LIGHT CONTROL SWITCH CONTINUITY
Switch positionTester connectionSpecified condition
OFF−No continuity
TAIL14 − 16Continuity
HEAD13 − 14 − 16Continuity
If continuity is not as specified, replace the switch.
2. INSPECT HEADLIGHT DIMMER SWITCH CONTINU-
ITY
Switch positionTester connectionSpecified condition
Flash7 − 8 − 16Continuity
Low beam16 − 17Continuity
High beam7 − 16Continuity
If continuity is not as specified, replace the switch.
3. INSPECT HEADLIGHT CONTROL RELAY CONTINU-
ITY
ConditionTester connectionSpecified condition
Constant3 − 4Continuity
Apply B+ between
terminals 3 and 4.1 − 2Continuity
If continuity is not as specified, replace the relay.
4. INSPECT TAILLIGHT CONTROL RELAY CONTINUITY
ConditionTester connectionSpecified condition
Constant1 − 2Continuity
Apply B+ between
terminals 1 and 2.3 − 5Continuity
If continuity is not as specified, replace the relay.
5. Light−on Warning System:
INSPECT INTEGRATION RELAY OPERATION
(a) Connect the positive (+) lead from the battery to terminal
1 and 12, the negative (−) lead to terminals 10.
(b) Check that the buzzer sounds when the negative (−) lead
from the battery is connected to terminal 6.
If operation is not as specified, replace the relay.
6. INSPECT DOOR COURTESY SWITCH CONTINU-
ITY(See pageBE−22)

N09214
DLC 3 DI−4
− DIAGNOSTICSENGINE
1996 RAV4 (RM447U)
By switching the ECM to check mode when trouble-
shooting, the technician can cause the MIL to light
up for a malfunction that is only detected once or
momentarily (TOYOTA hand−held tester only) (See
page DI−3).
*2 trip detection logic:
When a logic malfunction is first detected, the mal-
function is temporarily stored in the ECM memory.
If the same malfunction is detected again during the
second drive test, this second detection causes the
MIL to light up.
The 2 trip repeats the same mode a 2nd time. (How-
ever, the IG switch must be turned OFF between the
1st trip and 2nd trip).
Freeze frame data:
Freeze frame data records the engine condition
when a misfire (DTC P0300 − P0304) or fuel trim
malfunction (DTC P0171, P0172), or other malfunc-
tion (first malfunction only), is detected.
Because freeze frame data records the engine
conditions (fuel system, calculator load, engine
coolant temperature, fuel trim, engine speed, ve-
hicle speed, etc.) when the malfunction is detected,
when troubleshooting it is useful for determining
whether the vehicle was running or stopped, the en-
gine warmed up or not, the air−fuel ratio lean or rich,
etc. at the time of the malfunction.
Priorities for Troubleshooting:
If troubleshooting priorities for multiple diagnostic
codes are given in the applicable diagnostic chart,
these should be followed.
If no instructions are given, troubleshoot DTC according to the
following priorities.
(1) DTC other than fuel trim malfunction (DTC P0171,
P0172), EGR (DTC P0401, P0402), and misfire
(DTC P0300 − P0304).
(2) Fuel trim malfunction (DTC P0171, P0172) and
EGR (DTC P0401, P0402).
(3) Misfire (DTC P0300 − P0304).
(b) Check the DLC3.
The vehicle’s ECM uses V.P.W. (Variable Pulse Width) for
communication to comply with SAE J1850. The terminal
arrangement of DLC3 complies with SAE J1962 and
matches the V.P.W. format.

− DIAGNOSTICSENGINE
DI−13
1996 RAV4 (RM447U)
(b) TOYOTA Enhanced Signals
TOYOTA hand−held tester displayMeasurement ItemNormal Condition *
MISFIRE RPMEngine RPM for first misfire rangeMisfire 0: 0 RPM
MISFIRE LOADEngine load for first misfire rangeMisfire 0: 9 g/r
INJECTORFuel injection time for cylinder No.1Idling: 1.9 − 3.3 ms
IAC DUTY RATIOIntake Air Control Valve Duty Ratio Opening
ratio rotary solenoid type IAC valveIdling: 25 − 60 %
STARTER SIGStarter SignalCranking: ON
A/C SIGA/C Switch SignalA/C ON: ON
PNP SWPark / Neutral Position Switch SignalP or N position: ON
ELCTRCL LOAD SIGElectrical Load SignalDefogger S/W ON: ON
STOP LIGHT SWStop Light Switch SignalStop light switch ON: ON
FC IDLFuel Cut Idle: Fuel cut when throttle valve fully
closed, during decelerationFuel cut operating: ON
FC TAUFuel Cut TAU: Fuel cut during very light loadFuel cut operating: ON
CYL#1
CYL#2
CYL#3
CYL#4
Abnormal revolution variation for each cylinder0 %
IGNITIONTotal number of ignitions for every 1,000
revolutions0 − 2,000
EGR SYSTEMEGR system operating conditionIdling: OFF
FUEL PUMPFuel Pump SignalIdling: ON
EVAP (PURGE) VSVEVAP VSV SignalVSV operating: ON
VAPOR PRESS VSVVapor Pressure VSV SignalVSV operating: ON
A/C CUT SIGA/C Cut SignalA/C S/W OFF: ON
TOTAL FT B1Total Fuel Trim Bank 1: Average value for fuel
trim system of bank 1Idling: 0.8 − 1.2
O2 LR B1, S1
Oxygen Sensor Lean Rich Bank 1, Sensor 1
Response time for oxygen sensor output to
switch from lean to rich.
Idling after warned up: 0 − 1,000 msec.
O2 RL B1, S1
Oxygen Sensor Rich Lean Bank 1, Sensor 1
Response time for oxygen sensor output to
switch from rich to lean.
Idling after warned up: 0 − 1,000 msec.
*: If conditions are specifically stated for ”Idling” , it means the shift lever is at N or P Position, the A/C switch
is OFF and all accessory switches are OFF.

− DIAGNOSTICSENGINE
DI−15
1996 RAV4 (RM447U) DTC No.
(See Page)
Detection ItemTrouble AreaMILMemory
P0172
(DI−48)System too Rich
(Fuel Trim)
Fuel line pressure
Injector blockage, leak
Oxygen sensor malfunction
Manifold absolute pressure sensor
Engine coolant temp. sensor
 *1
P0300
(DI−51)Random / Multiple
Cylinder Misfire DetectedIgnition system
Injector
Fuel line pressure
EGR
Compression pressure
Valve clearance not to specification
Valve timing
Manifold absolute pressure sensor
Engine coolant temp. sensor
 *2P0301
P0302
P0303
P0304
(DI−51)Misfire Detected
− Cylinder 1
− Cylinder 2
− Cylinder 3
− Cylinder 4
P0325
(DI−56)Knock Sensor 1 Circuit
MalfunctionOpen or short in knock sensor 1 circuit
Knock sensor 1 (looseness)
ECM
 *1
P0335
(DI−59)Crankshaft Position Sensor
”A” Circuit Malfunction
Open or short in crankshaft position sensor circuit
Crankshaft position sensor
Starter
ECM
 *1
P0336
(DI−62)Camshaft Position Sensor
Circuit Range / PerformanceDistributor
ECM malfunction (for back up) *1
P0340
(DI−63)Camshaft Position Sensor
Circuit Malfunction
Open or short in camshaft position sensor circuit
Camshaft position sensor
Starter
ECM
 *1
P0401
(DI−65)Exhaust Gas Recirculation
Flow Insufficient Detected
EGR valve stuck close
Open or short in VSV circuit for EGR
Vacuum or EGR hose disconnected
Manifold absolute pressure sensor
EGR VSV open or close malfunction
ECM
 *1
P0402
(DI−71)Exhaust Gas Recirculation
Flow Excessive Detected
EGR valve stuck open
Vacuum or EGR hose is connected to wrong post
Manifold absolute pressure sensor
ECM
 *1
P0420
(DI−73)Catalyst System Efficiency
Below ThresholdThree−way catalytic converter
Open or short in oxygen sensor circuit
Oxygen sensor
 *1
P0440
(DI−76)Evaporative Emission Control
System Malfunction
Vapor pressure sensor
Fuel tank cap incorrectly installed
Fuel tank cap cracked or damaged
Vacuum hose cracked, holed, blocked, damaged or
disconnected
Hose or tube cracked, holed, damaged or loose
Fuel tank cracked, holed, or damaged
Charcoal canister cracked, holed or damaged
 *1
*1: MIL lights up
*
2: MIL lights up or blinking

− DIAGNOSTICSENGINE
DI−19
1996 RAV4 (RM447U) FC (E6−14) − E1 (E4−14)
G−R ↔ BRIG switch ON9 ∼ 14
EGR (E4−23) − E1 (E4−14)B−W ↔ BRIG switch ON0 ∼ 3
ISCC (E4−9) − E1 (E4−14)B−Y ↔ BRIG switch ON
Disconnect E4 of ECM connector9 ∼ 14
ISCO (E4−10) − E1 (E4−14)B−L ↔ BRIG switch ON
Disconnect E4 of ECM connector9 ∼ 14
OX1 (E5−6) − E1 (E4−14)B ↔ BRMaintain engine speed at 2,500 rpm for 2 mins. after
warning up.Pulse generation
OX2 (E5−5) − E1 (E4−14)B ↔ BRMaintain engine speed at 2,500 rpm for 2 mins. after
warning up.Pulse generation
KNK (E5−10) − E1 (E4−14)B ↔ BRIdlingPulse generation
(See page DI−56)
* NSW (E6−22) − E1 (E4−14)B−W ↔ BR
IG switch ON
Other shift position in ”P” , ”N” position9 ∼ 14
IG switch ON
Shift position in ”P” , ”N” position0 ∼ 3.0
SPD (E6−9) − E1 (E4−14)V−W ↔ BRIG switch ON
Rotate driver wheel slowly.Pulse generation
(See page DI−94)
TE1 (E5−15) − E1 (E4−14)L−W ↔ BRIG switch ON9 ∼ 14
W (E6−5) − E1 (E4−14)G−R ↔ BRIdling9 ∼ 14
IG switch ONBelow 3.0
AC (E6−10) − E1 (E4−14)Y−G ↔ BRIdling, A/C switch ONBelow 2.0
Idling, A/C switch OFF9 ∼ 14
ACT (E6−21) − E1 (E4−14)R−Y ↔ BRIdling, A/C switch ON9 ∼ 14
Idling, A/C switch OFFBelow 2.0
* OD2 (E6−7) − E1 (E4−14)LG ↔ BRIG switch ON, O/D main switch pushed out9 ∼ 14
IG switch ON, O/D main switch pushed in0 ∼ 3
* OD1 (E6−20) − E1 (E4−14)Y−B ↔ BRIG switch ON, Cruise control ECU no request O/D cut9 ∼ 14
IG switch ON, Cruise control ECU request O/D cut0 ∼ 3
EVP (E4−22) − E1 (E4−14)P ↔ BRIG switch ON9 ∼ 14
TPC (E5−8) − E1 (E4−14)R−W ↔ BRIG switch ON9 ∼ 14
PTNK (E5−7) − E2 (E5−9)L−Y ↔ BR
IG switch ON, Disconnect vacuum hose from vapor
pressure sensor2.9 ∼ 3.7
Apply vacuum
(4.0 kPa, 30 mmHg, 1.18 in. Hg)
(less than 66.7 kPa, 500 mmHg, 19.7 in. Hg)
Below 0.5
ELS (E6−17) − E1 (E4−14)B ↔ BRDefogger switch and taillight switch ON7.5 ∼ 14
Defogger switch and taillight switch OFF0 ∼ 1.5
SDL (E6−16) − E1 (E4−14)W ↔ BRDuring transmissionPules generation
*: A/T only

− DIAGNOSTICSENGINE
DI−51
1996 RAV4 (RM447U)
DTC P0300 Random / Multiple Cylinder Misfire
Detected
DTC P0301 Cylinder 1 Misfire Detected
DTC P0302 Cylinder 2 Misfire Detected
DTC P0303 Cylinder 3 Misfire Detected
DTC P0304 Cylinder 4 Misfire Detected
CIRCUIT DESCRIPTION
Misfire: The ECM uses the crankshaft position sensor and camshaft position sensor to monitor changes in
the crankshaft rotation for each cylinder.
The ECM counts the number of times the engine speed change rate indicates that misfire has occurred. And
when the misfire rate equals or exceeds the count indicating that the engine condition has deteriorated, the
MIL lights up.
If the misfire rate is high enough and the driving conditions will cause catalyst overheating, the MIL blinks
when misfiring occurs.
DTC No.DTC Detecting ConditionTrouble Area
P0300Misfiring of random cylinder is detected during any particular
200 or 1,000 revolutionsIgnition system
Injector
Fuel line pressure
EGR
Compression pressure
Valve clearance not to specification
Valve timing
Manifold absolute pressure sensor
Engine coolant temp. sensor
P0301
P0302
P0303
P0304
For any particular 200 revolutions of the engine, misfiring is
detected which can cause catalyst overheating
(This causes MIL to blink)
For any particular 1,000 revolutions of the engine, misfiring is
detected which causes a deterioration in emissions
(2 trip detection logic)
HINT:
When the 2 or more codes for a misfiring cylinder are recorded repeatedly but no Random Misfire code is
recorded, it indicates that the misfires were detected and recorded at different times.
DI3ZO−01

DI−54
− DIAGNOSTICSENGINE
1996 RAV4 (RM447U)
3 Check injector resistance of misfiring cylinder (See page SF−21).
NG Replace injector.
OK
Check for open and short in harness and con-
nector between injector and ECM (See page
IN−30).
4 Check fuel pressure (See page SF−5).
NG Check and repair fuel pomp, pressure regulator,
fuel pipe line and filter (See page SF−1).
OK
5 Check injector injection (See page SF−21).
NG Replace injector.
OK
6 Check EGR system (See page SF−45).
NG Repair EGR system.
OK
7 Check manifold absolute pressure sensor and engine coolant temp. sensor (See
page DI−21, DI−29).

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