coolant temperature TOYOTA RAV4 1996 Service Repair Manual

V08467
18
Noise NOISE PRODUCED WHEN ENGINE STARTS
Whistling noise which becomes high−pitched
when accelerator strongly depressed, disappears
shortly after engine stops.Ye s
Generator noise.
No
Whining noise occurs when A/C is operating.Ye s
A/C noise.
Scratching noise occurs during sudden
acceleration, driving on rough roads or when
ignition switch is turned on.No
Ye s
Fuel gauge noise.
No
Clicking sound heard when horn button is
pressed, then released. Whirring/grating sound
when pushed continuously.Ye s
Horn noise.
No
Murmuring sound stops when engine stops.
NoYe s
Ignition noise.
Tick−tock noise, occurs in co−ordination with
blinking of flasher.Ye s
Turn signal noise.
No
Noise occurs during window washer operation.Ye s
Washer noise.
No
Scratching noise occurs while engine is running,
continues a while even after engine stops.
NoEngine coolant temperature gauge noise. Ye s
Scraping noise in time with wiper beat.
NoYe s
Wiper noise.
Other type of noise.
− BODY ELECTRICALAUDIO SYSTEM
BE−79
1996 RAV4 (RM447U)

S01294
CO0BS−03
S01279
Disconnect
S01277
93°C
S01290
Ammeter
Battery
S01291
Ammeter
Battery CO−18
− COOLINGELECTRIC COOLING FAN
1996 RAV4 (RM447U)
ELECTRIC COOLING FAN
ON−VEHICLE INSPECTION
1. CHECK COOLING FAN OPERATION WITH LOW TEM-
PERATURE (Below 83°C (181°F))
(a) Turn the ignition switch ON.
(b) Check that the cooling fan stops.
If not, check the cooling fan relay and ECT switch, and check
for a separated connector or severed wire between the cooling
fan relay and ECT switch.
(c) Disconnect the ECT switch connector.
(d) Check that the cooling fan rotates.
If not, check the fan main relay, cooling fan relay, cooling fan,
fuses, and check for short circuit between the cooling fan relay
and ECT switch.
(e) Reconnect the ECT switch connector.
2. CHECK COOLING FAN OPERATION WITH HIGH TEM-
PERATURE (Above 93°C (199°F))
(a) Start the engine, and raise coolant temperature to above
93°C (199°F).
(b) Check that the cooling fan rotates.
If not, replace the ECT switch.
3. INSPECT NO.1 COOLING FAN
(a) Disconnect the cooling fan connector.
(b) Connect battery and ammeter to the cooling fan connec-
tor.
(c) Check that the cooling fan rotates smoothly, and check
the reading on the ammeter.
Standard amperage: 10.9 − 13.9 A
(d) Reconnect the cooling fan connector.
4. INSPECT NO.2 COOLING FAN
(a) Disconnect the cooling fan connector.
(b) Connect battery and ammeter to the cooling fan connec-
tor.
(c) Check that the cooling fan rotates smoothly, and check
the reading on the ammeter.
Standard amperage: 9.1 − 11.1 A
(d) Reconnect the cooling fan connector.

S01280ECT Switch
CO0BY−01
P05962
Ohmmeter
− COOLINGENGINE COOLANT TEMPERATURE (ECT) SWITCH
CO−25
1996 RAV4 (RM447U)
ENGINE COOLANT
TEMPERATURE (ECT) SWITCH
INSPECTION
1. DRAIN ENGINE COOLANT
2. REMOVE ECT SWITCH
3. INSPECT ECT SWITCH
(a) Using an ohmmeter, check that there is no continuity be-
tween the terminals when the coolant temperature is
above 93°C (199°F).
(b) Using an ohmmeter, check that there is continuity be-
tween the terminals when the coolant temperature is be-
low 83°C (181°F).
If continuity is not as specified, replace the switch.
4. REINSTALL ECT SWITCH
5. REFILL WITH ENGINE COOLANT
6. START ENGINE AND CHECK FOR COOLANT LEAKS

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.

DI−12
− DIAGNOSTICSENGINE
1996 RAV4 (RM447U)
7. ENGINE OPERATING CONDITION
NOTICE:
The value given below for ”Normal Condition” are representative values, so a vehicle may still be
normal even it its value varies from those listed here. So do not decide whether a part is faulty or not
solely according to the ”Normal Condition” here.
(a) CARB Mandated Signals
TOYOTA hand−held tester displayMeasurement ItemNormal Condition *
FUEL SYS #1
Fuel System Bank 1
OPEN: Air−fuel ratio feedback stopped
CLOSED: Air−fuel ratio feedback operating
Idling after warning up: CLOSED
CALC LOAD
Calculator Load:
Current intake air volume as a proportion of max.
intake air volumeIdling: 20.7 − 48.4 %
Racing without load (2,500 rpm) : 17.7 − 45.3 %
COOLANT TEMPEngine Coolant Temperature Sensor ValueAfter warning up: 80 − 95°C (176 − 203°F)
SHORT FT #1Short−term Fuel Trim Bank 10 ± 20 %
LONG FT #1Long−term Fuel Trim Bank 10 ± 20 %
ENGINE SPDEngine SpeedIdling: 700 ± 50 rpm
VEHICLE SPDVehicle SpeedVehicle Stopped: 0 km/h (0 mph)
IGN ADVANCEIgnition Advance
Ignition Timing of Cylinder No.1Idling: BTDC 0 − 10°
INTAKE AIRIntake Air Temperature Sensor ValueEquivalent to Ambient Temp.
MAPAbsolute Pressure Inside Intake ManifoldIdling: 21 − 49 kPa
Racing without load (2,500 rpm): 17 − 46 kPa
THROTTLE POS
Voltage Output of Throttle Position Sensor
Calculated as a Percentage
0V → 0 %, 5V → 100 %Throttle Fully Closed: 6 − 16 %
Throttle Fully Open: 64 − 98 %
O2S B1, S1Voltage Output of Oxygen Sensor
Bnak 1,Sensor 1Idling : 0.1 − 0.9 V
O2FT B1, S1Oxygen Sensor Fuel Trim Bank 1, Sensor 1
(Same as SHORT FT #1)0 ± 20 %
O2S B1, S2Voltage Output of Oxygen Sensor
Bank 1, Sensor 2Driving 50 km/h (31 mph): 0.1 − 0.9 V
*: If no 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.

P19745
Intake Air Temp. Sensor
Y−B
BRE5
E5E2 THAR5V
E1 93ECM
2
1
DI−26
− DIAGNOSTICSENGINE
1996 RAV4 (RM447U)
WIRING DIAGRAM
INSPECTION PROCEDURE
HINT:
If DTC ”P0105” (Manifold Absolute Pressure / Barometric Pressure Circuit Malfunction), ”P0110” (Intake Air
Temp. Circuit Malfunction), ”P0115” (Engine Coolant Temp. Circuit Malfunction), ”P0120” (Throttle / Pedal
Position Sensor / Switch ”A” Circuit Malfunction) are output simultaneously, E2 (sensor ground) may be
open.
1 Connect the OBDII scan tool or TOYOTA hand−held tester, and read value of
intake air temperature.
PREPARATION:
(a) Connect the OBDII scan tool or TOYOTA hand−held tester to the DLC3.
(b) Turn ignition switch ON and OBDII scan tool or TOYOTA hand−held tester main switch ON.
CHECK:
Read temperature value on the OBDII scan tool or TOYOTA hand−held tester.
OK:
Same as actual intake air temperature.
HINT:
If there is open circuit, OBDII scan tool or TOYOTA hand−held tester indicates − 40°C (− 40°F).
If there is short circuit, OBDII scan tool or TOYOTA hand−held tester indicates 140°C (284°F) or more.
NG− 40°C (− 40°F) .... Go to step 2.
140°C (284°F) .... Go to step 4.
OK
Check for intermittent problems.
(See page DI−3).

P19746
Engine Coolant Temp. Sensor
W
BRE5
E5E2THW5V
E1 94ECM
2
1
− DIAGNOSTICSENGINE
DI−29
1996 RAV4 (RM447U)
DTC P0115 Engine Coolant Temp. Circuit Malfunction
CIRCUIT DESCRIPTION
A thermistor built into the engine coolant temperature sensor changes the resistance value according to the
engine coolant temperature.
The structure of the sensor and connection to the ECM is the same as in the intake air temp. circuit malfunc-
tion shown on page DI−25.
If the ECM detects the DTC P0115, it operates the fail safe function in which the engine coolant temp. is
assumed to be 80°C (176°F).
DTC No.DTC Detecting ConditionTrouble Area
P0115Open or short in engine coolant temp. sensor circuit
Open or short in engine coolant temp. sensor circuit
Engine coolant temp. sensor
ECM
HINT:
After confirming DTC P0115 use the OBDII scan tool or TOYOTA hand−held tester to confirm the engine
coolant temperature from ”CURRENT DATA”.
Temperature DisplayedMalfunction
− 40°C (− 40°F)Open circuit
140°C (284°F) or moreShort circuit
WIRING DIAGRAM
INSPECTION PROCEDURE
HINT:
If DTC ”P0105” (Manifold Absolute Pressure / Barometric Pressure Circuit Malfunction), ”P0110” (Intake Air
Temp. Circuit Malfunction), ”P0115” (Engine Coolant Temp. Circuit Malfunction), ”P0120” (Throttle / Pedal
Position Sensor / Switch ”A” Circuit Malfunction) are output simultaneously, E2 (sensor ground) may be
open.
DI3ZF−01

A00395
Engine Coolant
Temp. Sensor
E5
E2
THW
5V
94ECM
E5E1
1 2
ON
DI−30
− DIAGNOSTICSENGINE
1996 RAV4 (RM447U)
1 Connect the OBDII scan tool or TOYOTA hand−held tester, and read value of en-
gine coolant temperature.
PREPARATION:
(a) Connect the OBDII scan tool or TOYOTA hand−held tester to the DLC3.
(b) Turn ignition switch ON and OBDII scan tool or TOYOTA hand−held tester main switch ON.
CHECK:
Read temperature value on the OBDII scan tool or TOYOTA hand−held tester.
OK:
Same as actual engine coolant temperature.
HINT:
If there is open circuit, OBDII scan tool or TOYOTA hand−held tester indicates − 40°C (− 40°F).
If there is short circuit, OBDII scan tool or TOYOTA hand−held tester indicates 140°C (284°F) or more.
NG− 40°C (− 40°F) .... Go to step 2.
140°C (284°F) or more .... Go to step 4.
OK
Check for intermittent problems
(See page DI−3).
2 Check for open in harness or ECM.
PREPARATION:
(a) Disconnect the engine coolant temp. sensor connector.
(b) Connect sensor wire harness terminals together.
(c) Turn ignition switch ON.
CHECK:
Read temperature value on the OBDII scan tool or TOYOTA
hand−held tester.
OK:
Temperature value: 140°C (284°F) or more.
OK Confirm good connection at sensor. If OK,
replace engine coolant temp. sensor.
NG

A00396
Engine Coolant
Temp. Sensor
E5E2
THW
5V
94ECM
E5
E1
12
ON
THWE2
A00397
Engine Coolant
Temp. Sensor
E5E2
THW
5V
94ECM
E5
E1
ON
− DIAGNOSTICSENGINE
DI−31
1996 RAV4 (RM447U)
3 Check for open in harness or ECM.
PREPARATION:
(a) Remove side trim cover. (See page SF−61).
(b) Connect between terminals THW and E2 of ECM connec-
tor.
HINT:
Engine coolant temp. sensor connector is disconnected. Be-
fore checking, do a visual and contact pressure check for the
ECM connector (See page IN−30).
(c) Turn ignition switch ON.
CHECK:
Read temperature value on the OBDII scan tool or TOYOTA
hand−held tester.
OK:
Temperature value: 140°C (284°F) or more
OK Open in harness between terminals E2 or THW,
repair or replace harness.
NG
Confirm good connection at ECM.
If OK, replace ECM.
4 Check for short in harness and ECM.
PREPARATION:
(a) Disconnect the engine coolant temp. sensor connector.
(b) Turn ignition switch ON.
CHECK:
Read temperature value on the OBDII scan tool or TOYOTA
hand−held tester.
OK:
Temperature value : − 40°C (− 40°F)
OK Replace engine coolant temp. sensor.
NG

A00398
Engine Coolant
Temp. Sensor
E2
THW
5V ECM
E1
ON
E5connector
DI−32
− DIAGNOSTICSENGINE
1996 RAV4 (RM447U)
5 Check for short in harness or ECM.
PREPARATION:
(a) Remove side trim cover. (See page SF−61).
(b) Disconnect the E5 connector of ECM.
HINT:
Engine coolant temp. sensor connector is disconnected.
(c) Turn ignition switch ON.
CHECK:
Read temperature value on the OBDII scan tool or TOYOTA
hand−held tester.
OK:
Temperature value : − 40°C (− 40°F)
OK Repair or replace harness or connector.
NG
Check and replace ECM
(See page IN−30).