2000 TOYOTA CAMRY coolant

This system utilizes an engine control module and maintains overall control of the engine, transmission and so on. An outline
of the engine control is explained here.
1. INPUT SIGNALS
(1) Engine coolant temp. signal circuit
The engine coolant temp. sensor detects the engine coolant temp. and has a built±in thermistor with a resistance which
varies according to the water temp. is input into TERMINAL THW of the engine control module as a control signal.
(2) Intake air temp. signal circuit
The intake air temp. sensor is installed in the mass air flow meter and detects the intake air temp., which is input as a
control signal into TERMINAL THA of the engine control module.
(3) Oxygen sensor signal circuit
The oxygen density in the exhaust gases is detected and input as a control signal into TERMINALS OXL1, OXR1
(Except California) and OXS of the engine control module. To maintain stable detection performance by the heated
oxygen sensor, a heater is used for warming the sensor. The heater is also controlled by the engine control module
(HTL, HTR (Except California) and HTS).
(4) RPM signal circuit
Camshaft position and crankshaft position are detected by the camshaft position sensor and crankshaft position sensor.
The camshaft position is input as a control signal to TERMINAL G22+ of the engine control module, and the engine
RPM is input into TERMINAL NE+.
(5) Throttle signal circuit
The throttle position sensor detects the throttle valve opening angle as a control signal, which is input into TERMINAL
VTA1 of the engine control module.
(6) Vehicle speed signal circuit
The vehicle speed sensor, installed inside the transmission, detects the vehicle speed and inputs a control signal into
TERMINAL SPD of the engine control module.
(7) Park/Neutral position SW signal circuit
The Park/Neutral position SW detects whether the shift position is in neutral, parking or not, and inputs a control signal
into TERMINAL STA of the engine control module.
(8) A/C SW signal circuit
The A/C control assembly (Automatic A/C) or A/C Amplifier (Manual A/C) inputs the A/C operations into TERMINAL A/C
of the engine control module as a control signal.
(9) Battery signal circuit
(California or w/ engine immobiliser and/or traction control)
Voltage is always supplies to TERMINAL BATT of the engine control module.
If you turn on the ignition SW, the current goes from TERMINAL MREL of the engine control module to the EFI relay and
put on the relay, and the voltage related to the engine control module operation is supplied to TERMINAL +B of the
engine control module through the EFI relay.
(Except California or w/ engine immobiliser and/or traction control)
Voltage is constantly applied to TERMINAL BATT of the engine control module. When the ignition SW is turned on,
voltage for engine control module start±up power supply is applied to TERMINAL +B of engine control module via EFI
relay.
(10) Intake air volume signal circuit
Intake air volume is detected by the mass air flow meter and a signal is input into TERMINAL VG of the engine control
module as a control signal.
(11) NSW signal circuit
To confirm whether the engine is cranking, the voltage applied to the starter motor during cranking is detected and the
signal is input into TERMINAL NSW of the engine control module as a control signal.
(12) Engine knock signal circuit
Engine knocking is detected by the knock sensor 1 and 2, then the signals are input into TERMINALS KNKR and KNKL
of the engine control module as a control signal.
(13) Air fuel ratio signal circuit (California)
The air fuel ratio is detected and input as a control signal into TERMINALS AFL+, AFR+ of the engine control module.
SYSTEM OUTLINE

E5 ENGINE COOLANT TEMP. SENSOR
1±2 : Approx. 15.04 kW (±20C, ±4F)
Approx. 5.74 kW (0C, 32F)
Approx. 2.45 kW (20C, 68F)
Approx. 1.15 kW (40C, 104F)
Approx. 0.584 kW (60C, 140F)
Approx. 0.318 kW (80C, 176F)
E7 (A), E8 (B), E9 (C), E10 (D), E11 (E)
ENGINE CONTROL MODULE
Voltage at engine control module wiring connector
BATT±E1 : Always 9.0±14.0 volts
+B±E1 :9.0±14.0 volts (Ignition SW at ON position)
VC±E2 : Always 4.5±5.5 volts (Ignition SW at ON position)
VTA1±E2 :0.3±0.8 volts (Ignition SW on and throttle valve fully closed)
:3.2±4.9 volts (Ignition SW on and throttle valve fully open)
VG±E2G :1.1±1.5 volts (Engine idling and A/C SW OFF position)
THA±E2 :0.5±3.4 volts (Engine idling and intake air temp. 20°C, 68°F)
THW±E2 :0.2±1.0 volts (Engine idling and engine coolant temp. 80°C, 176°F)
IGF±E1 :4.5±5.5 volts (Ignition SW at ON position)
Pulse generation (Engine idling)
G22+±NE± : Pulse generation (Engine idling)
NE+±NE± : Pulse generation (Engine idling)
NSW±E1 :9.0±14.0 volts (Ignition SW on and other shift position in P or N position)
Below 3.0 volts (Ignition SW on and shift position in P or N position)
SPD±E1 : Pulse generation (Ignition SW on and rotate driving wheel slowly)
TC±E1 :9.0±14.0 volts (Ignition SW at ON Position)
W±E1 : Below 3.0 volts
A/C±E1 : Below 2.0 volts (Engine idling and A/C SW on)
9.0±14.0 volts (A/C SW off)
ACT±E1 :9.0±14.0 volts (Engine idling and A/C SW on)
Below 2.0 volts (A/C SW off)
ACIS±E01 :9.0±14.0 volts (Ignition SW at ON position)
STA±E1 :6.0 volts or more (Engine cranking)
THG±E2 :4.5±5.5 volts (Ignition SW at ON position)
ELS±E1 :7.5±14.0 volts (Taillight SW at ON position)
0±1.5 volts (Taillight SW at OFF position)
ELS2±E1 :7.5±14.0 volts (Defogger SW at ON position)
0±1.5 volts (Defogger SW at OFF position)
EGR±E01 :9.0±14.0 volts (Ignition SW at ON position)
FC±E1 :9.0±14.0 volts (Ignition SW at ON position)
0±3.0 volts (Engine idling)
EVP1±E01 :9.0±14.0 volts (Ignition SW at ON position)
CF±E1 :9.0±14.0 volts (Electric cooling fan is operating on high speed)
0±2.0 volts (Electric cooling fan is operating on low speed or off)
TACH±E1 : Pulse generation (Engine idling)
TPC±E1 :9.0±14.0 volts (Ignition SW on and disconnect the vacuum hose from the vapor pressure sensor)
PTNK±E1 :3.0±3.6 volts (Ignition SW at ON position)
1.3±2.1 volts (Ignition SW on and apply vacuum 2.0 kpa (15.0 mmHg, 0.6 in.Hg)
STP±E1 :7.5±14.0 volts (Ignition SW on and brake pedal depressed)
Below 1.5 volts (Ignition SW on and brake pedal released)
SIL±E1 : Pulse generation (During transmission)
RSC, RSO±E01 :9.0±14.0 volts (Ignition SW on and disconnect E 7 of engine control module connector)
KNKL, KNKR±E1 : Pulse generation (Engine idling)
HTS, HTL, HTR±E03 :9.0±14.0 volts (Ignition SW at ON position)
0±3.0 volts (Engine idling)
OXS, OXL, OXR±E1 : Pulse generation (Maintain engine speed at 2500 rpm for two minutes after warning up)
IGT1, IGT2, IGT3±E1 : Pulse generation (Engine idling)
#10, #20, #30, #40, #50, #60±E01 :9.0±14.0 volts (Ignition SW at ON position)
Pulse generation (Engine idling)
SERVICE HINTS

ENGINE CONTROL (5S±FE)
1 2
2 1
2 1
1
I 2 I 2
I 2
I 2
I 2 C 10 C9C23 C22 B 8B 13 C2B14 B6
B 8B1B9 B 10 B2B3B4
1 2
1 2 3 114 B B B B
2 13 2 3 1
1 3 2223 BB
BR
B±Y B±YBR BR B±Y(
*6) B±Y B±Y
BR BRY
G±BY±B
BR BRB±Y Y
LG
BR BRY
P
BRYW
B±O
P±B
V±WV
W
G(
*5)
BRB BRB±Y B±Y B±Y
PIM VC E2
E2 VCC PTNKISCO ISCC EGR EVP TPCKNK HTAF AF± AF+
PTNK VC VTA E2 PIM THA THW
VC VTA E2
(
*5)
(
*5)
(
*5)
J19
JUNCTION
CONNECTOR
IDLE AIR CONTROL VALVE
VSV (
EGR)
VSV (
EVAP) VSV
(
VAPOR PRESSURE SENSOR)
KNOCK SENSOR 1
AIR FUEL RATIO SENSOR I 1
V 4
V 5 V 7
K 1
A11
VAPOR PRESSURE
SENSORMANIFOLD ABSOLUTE
PRESSURE SENSOR V 1M 1
INTAKE AIR TEMP. SENSOR
ENGINE COOLANT TEMP. SENSORI14
E 5
ENGINE CONTROL MODULEB E 7 E 8ACE 9
(
SHIELDED)
(
SHIELDED)
+B AF+
AF± HT B±Y
ID1 10
B±Y
ID1 1
II4 5
V V
C 7C6B15 C3 B 16B 12 C2B14 B6(
*1)
(
*2)
II47
ID12 ID15II48
ID16B 7B1B9 B 11 B2B3B4
P
Y
BR P P
Y Y
BR , , DE10 ,
(
*1)
(
*2)
I 6 II23
BR
THROTTLE P OSI TI ON
SENSOR T 2BR
BR
BR
B±W(
*3)
O(
*4) (
*5)
(
*5) L(
*3)
W(
*4)

ENGINE CONTROL (5S±FE)
This system utilizes an engine control module and maintains overall control of the engine, transmission and so on. An outline
of the engine control is explained here.
1. INPUT SIGNALS
(1) Engine coolant temp. signal circuit
The engine coolant temp. sensor detects the engine coolant temp. and has a built±in thermistor with a resistance which
varies according to the engine coolant temp. thus the engine coolant temp. is input in the form of a control signal into
TERMINAL THW of the engine control module.
(2) Intake air temp. signal circuit
The intake air temp. sensor detects the intake air temp., which is input as a control signal into TERMINAL THA of the
engine control module.
(3) Oxygen sensor signal circuit
The oxygen density in the exhaust gases is detected and input as a control signal into TERMINAL OX1 (except
California) and OX2 of the engine control module.
(4) RPM signal circuit
Camshaft position and crankshaft position are detected by the camshaft position sensor and crankshaft position sensor.
Camshaft position is input as a control signal to TERMINAL G+ of the engine control module, and engine RPM is input
into TERMINAL NE+.
(5) Throttle signal circuit
The throttle position sensor detects the throttle valve opening angle, which is input as a control signal into TERMINAL
VTA of the engine control module.
(6) Vehicle speed signal circuit
The vehicle speed sensor, installed inside the transmission, detects the vehicle speed and inputs a control signal into
TERMINAL SPD of the engine control module.
(7) Park/Neutral position SW signal circuit (A/T)
The Park/Neutral position SW detects whether the shift position are in neutral, parking or not, and inputs a control signal
into TERMINAL STA of the engine control module.
(8) A/C SW signal circuit
The A/C amplifier function is built in the engine control module. The A/C SW signal inputs into the TERMINAL A/C SW of
the engine control module.
(9) Battery signal circuit
Voltage is constantly applied to TERMINAL BATT of the engine control module. When the ignition SW is turned on, the
voltage for engine control module start±up power supply is applied to TERMINAL +B of engine control module via EFI
relay.
(10) Intake air volume signal circuit
Intake air volume is detected by the manifold absolute pressure sensor (for manifold pressure) and is input as a control
signal into TERMINAL PIN of the engine control module.
(11) Starter signal circuit
To confirm whether the engine is cranking, the voltage applied to the starter motor during cranking is detected and the
signal is input into TERMINAL NSW of the engine control module as a control signal.
(12) Engine knock signal circuit
Engine knocking is detected by knock sensor 1 and the signal is input into TERMINAL KNK as a control signal.
(13) Electrical load signal circuit
The signal when systems such as the rear window defogger, headlights, etc. Which cause a high electrical burden are
on is input to TERMINAL ELS as a control signal.
(14) Air fuel ratio signal circuit (California)
The air fuel ratio is detected and input as a control signal into TERMINAL AF+ of the engine control module.
SYSTEM OUTLINE

2. CONTROL SYSTEM
*SFI system
The SFI system monitors the engine condition through the signals, which are input from each sensor (Input signals from
(1) to (14) etc.) to the engine control module. The best fuel injection volume is decided based on this data and the
program memorized by the engine control module, and the control signal is output to TERMINALS #10, #20, #30 and
#40 of the engine control module to operate the injector. (Inject the fuel). The SFI system produces control of fuel
injection operation by the engine control module in response to the driving conditions.
*ESA system
The ESA system monitors the engine condition through the signals, which are input to the engine control module from
each sensor (Input signals from (1), (2), (4) to (12) etc.) the best ignition timing is detected according to this data and the
memorized data in the engine control module, and the control signal is output to TERMINALS IGT1 and IGT2. This
signal controls the igniter to provide the best ignition timing for the driving conditions.
*Idle Air Control system
The IAC system (Step motor type) increases the RPM and provides idling stability for fast idle±up when the engine is
cold and when the idle speed has dropped due to electrical load, etc. The engine control module evaluates the signals
from each sensor (Input signals (1), (4) to (8), (13) etc.), outputs current to TERMINALS ISCO and ISCC, and controls
the idle air control valve.
*Fuel pump control system
The engine control module operation outputs to TERMINAL FC and controls the CIR OPN relay. Thus controls the fuel
pump drive speed in response to conditions.
*EGR control system
The EGR cut control system controls the VSV (EGR) by evaluating the signals from each sensor which are input to the
engine control module (Input signals (1), (5), (6), (9) etc.) and by sending output to TERMINAL EGR of the engine
control module.
*A/C conditioning operation system
In addition to the conventional A/C cut control, the engine control module performs the air conditioning operation as well
since the A/C amplifier function is built in it.
3. DIAGNOSIS SYSTEM
With the diagnosis system, when there is a malfunctioning in the engine control module signal system, the malfunction
system is recorded in the memory. The malfunctioning system can then be found by reading the display (Code) of the
malfunction indicator lamp.
4. FAIL±SAFE SYSTEM
When a malfunction occurs in any system, if there is a possibility of engine trouble being caused by continued control based
on the signals from that system, the fail±safe system either controls the system by using data (Standard values) recorded in
the engine control module memory or else stops the engine.
E7 (A), E8 (B), E9 (C), E10 (D) ENGINE CONTROL MODULE
Voltage at engine control module wiring connector
BATT±E1 : Always 9.0±14.0 volts
+B±E1 :9.0±14.0 volts (Ignition SW at ON position)
VC±E2 :4.5± 5.5 volts (Ignition SW at ON position)
VTA±E2 :0.3± 0.8 volts (Ignition SW on and throttle valve fully closed)
3.2±4.9 volts (Ignition SW on and throttle valve open)
PIM±E2 :3.3± 3.9 volts (Ignition SW at ON position)
THA±E2 :0.5±3.4 volts (Ignition SW on and intake air temp. 20°C, 68°F)
THW±E2 :0.2± 1.0 volts (Ignition SW on and coolant temp. 80°C, 176°F)
STA±E1 :6.0±14.0 volts (Engine cranking)
W±E1 :9.0±14.0 volts (No trouble and engine running)
TE1±E1 :9.0±14.0 volts (Ignition SW at ON position)
NSW±E1 :0± 3.0 volts (Ignition SW on and Park/Neutral position SW position P or N position)
9.0±14.0 volts (Ignition SW on and except Park/Neutral position SW position P or N position)
IGT1, IGT2±E1 : Pulse generation (Engine cranking or idling)
#10, #20, #30, #40±E01, E02 :9.0±14.0 volts (Ignition SW at ON position)
RESISTANCE AT ENGINE CONTROL MODULE WIRING CONNECTORS
(Disconnect wiring connector)
VC±E2 :2.5±5.0 kW
THA±E2 :2.21±2.69 kW (Intake air temp. 20°C, 68°F)
THW±E2 :0.29±0.354 kW (Coolant temp. 80°C, 176°F)
SERVICE HINTS

ELECTRONICALLY CONTROLLED TRANSMISSION AND A/T INDICATOR
15A
EFIFROM POWER SOURCE S YS TEM (
SEE PAGE 50)
2J 815A
STOP
1C 7
23 15
2F 42J2
1R 4
1R 51 2
1 2
2 1
A 15 A 1D 2D23 D14 D 18
E 7E9E19 E20 E14 E26 A B
B BI 2
1 2
EBA
63241 A3
G±WB±YB±Y W± B W±B
G± W G±W W
BR
BR G± BL Y
BR L±B L±B
V
P±L
B±Y
W±L
R
G GJUNCTION
CONNECTORB J27 J28AEFI RELAY
SLN+ NC2+ NC2± BA TTVC
STOP LIGHT SW
THROTTLE POSI TI ON
SENSOR
ENGINE COOLANT TEMP. SENSOR
ELECTRONICALLY CONTROLLED
TRANSMISSION SOLENOID
VEHICLE SPEED SENSOR
(
ELECTRONICALLY CONTROLLED
TRANSMISSION)
E 3
V 3S 6
T 2
E 5 B
W
Y
L
R
S2 S1 SL SLN± SLN+ BB24
CRUISE CONTROL ECU C156 13 14
L±BL±R
Y±B
ECT IDL ODA ENGINE CONTROL MODULEB E 7 E 8ADE10 EE11 A 16
B±Y
+B 2C 5
W± B W±B
STP
VTA1
THW IDLO
OD1
SLN± JUNCTION
CONNECTOR J26
L±B5A
IGN
1W 7
A 2
B±RB±R
2K 7
A 8
B±W B±W
C CJUNCTION
CONNECTOR J35
IGSW
S1 SLE2
S25A
STARTER
1J 3
B 20
B±WB±W
B BJUNCTION
CONNECTOR J29
II27
,
,
A A
B C
JUNCTION
CONNECTORB J27 J28A
, , , MRELNSW
4E8

(1MZ±FE)
Previous automatic transaxle have selected each gear shift using the mechanically controlled throttle hydraulic pressure,
governor hydraulic pressure and lock±up hydraulic pressure. The electronically controlled transmission, however, electrically
controls the line pressure and lock±up pressure etc., through the solenoid valve. Engine control module control of the
solenoid valve based on the input signals from each sensor makes smooth driving possible by shift selection for each gear
which is most appropriate to the driving conditions at that time.
1. GEAR SHIFT OPERATION
During driving, the engine control module selects the shift for each gear which is most appropriate to the driving conditions,
based on input signals from the engine coolant temp. sensor to TERMINAL THW of the engine control module, and also the
input signals to TERMINAL NC2+ of the engine control module from the vehicle speed sensor devoted to the O/D direct
clutch. Current is then output to the electronically controlled transmission solenoid. When shifting to 1st speed, current flows
from TERMINAL S1 of the engine control module to TERMINAL 3 of the electronically controlled transmission solenoid to
GROUND, and continuity to the No.1 solenoid causes the shift.
For the 2nd speed, current flows from TERMINAL S1 of the engine control module to TERMINAL 3 of the electronically
controlled transmission solenoid to GROUND, and from TERMINAL S2 of the engine control module to TERMINAL 6 of the
electronically controlled transmission solenoid to GROUND, and continuity to solenoids No.1 and No.2 causes the shift.
For the 3rd speed, there is no continuity to No.1 solenoid, only to No.2, causing the shift.
Shifting into 4th speed (Overdrive) takes place when there is no continuity to either No.1 or No.2 solenoid.
2. LOCK±UP OPERATION
When the engine control module judges from each signal that lock±up operation conditions have been met, current flows
from TERMINAL SL of the engine control module to TERMINAL 2 of the electronically controlled transmission solenoid to
GROUND, causing continuity to the lock±up solenoid and causing lock±up operation.
3. STOP LIGHT SW CIRCUIT
If the brake pedal is depressed (Stop light SW on) when driving in lock±up condition, a signal is input to TERMINAL STP of
the engine control module, the engine control module operates and continuity to the lock±up solenoid is cut.
4. OVERDRIVE CIRCUIT
*Overdrive on
When the O/D main SW is turned on (O/D off indicator light turns off), a signal is input to TERMINAL OD2 of the engine
control module and engine control module operation causes gear shift when the conditions for overdrive are met.
*Overdrive off
When the O/D main SW is turned to off (O/D off indicator light turns on), the current flowing through the O/D off indicator
light flows through the O/D main SW to GROUND. Causing the indicator light to light up. At the same time, a signal is
input to TERMINAL OD2 of the engine control module and engine control module operation prevents shift into overdrive.
E7 (A), E8 (B), E10 (D), E11 (E) ENGINE CONTROL MODULE (TURN ON THE IGNITION SW)
S1, S2±E1 :9.0±14.0 volts with the solenoid on
0±1.5 volts with the solenoid off
L±E1 :7.5±14.0 volts with the shift lever at L position
2±E1 :7.5±14.0 volts with the shift lever at 2 position
R±E1 :7.5±14.0 volts with the shift lever at R position
STP±E1 :7.5±14.0 volts with the brake pedal depressed
THW±E2 :0.2±1.0 volts with the engine coolant temp. 80°C (176°F)
VAT1±E2 :0.3±0.8 volts with the throttle valve fully closed
3.2±4.9 volts with the throttle valve fully opened
VC±E2 :4.5±5.5 volts
OD2±E1 :9.0±14.0 volts with the O/D main SW turned off
0±3.0 volts with the O/D main SW turned on
+B±E1 :9.0±14.0 volts
OD1±E1 :9.0±14.0 volts
E3 ELECTRONICALLY CONTROLLED TRANSMISSION SOLENOID
2, 3, 6±GROUND : Each 11±15 W
O2 O/D MAIN SW
2±4 : Closed with the O/D main SW off, open with the O/D main SW on
SYSTEM OUTLINE
SERVICE HINTS

ELECTRONICALLY CONTROLLED TRANSMISSION AND A/T INDICATOR
15A
EFIFROM POWER SOURCE SYSTEM (
SEE PAGE 50)
2J 815A
STOP
1C 7
23 15
2F 42J2
1R 4
1R 51 2
1 2
2 1
A 4 A 1B 1B11 B4 B 9
C 21 C8C20 C24 A B
B BI 2
EBEC A
A A3
AA
G±WB±YB±Y W±B W± B
G± W G± W W
BR
BR G±BLGY
BR L±B L±B
V
P
BR BREFI
RELAY
BATTVC
STOP LIGHT SW
THROTTLE POSITION
SENSOR
ENGINE COOLANT TEMP. SENSORS 6
T 2
E 5 B
W
S2 S1 II2 7 A 3A18
CRUISE CONTROL ECU C156 13 14
L±BL±R
Y± B
ECT IDL ODA ENGINE CONTROL MODULEB ACD A 12
B±Y
+B
JUNCTION
CONNECTOR J23STP
VTA
THW IDLO
OD 1
E1
JUNCTION
CONNE CTOR J25 L±B5A
IGN
1W 7
B±R
2K 7
B±W B±W
IGSW
S1 SLE2
S2B 4 B 9 B 10 B 1 A 9 A 1 A 2 D 7 A 12(
*1)
(
*2) A A
B C
SL
NO. 2
NO. 1
LOCK±UP
B 1B3A1
E 3
ELECTRONICALLY CONTROLLED
TRANSMISSION SOLENOIDB A, E 4C 1 C 7 C 6 A 20 A 3E 7 , E 8 , E 9 , E10
B± R
(
*2)
(
*1)
J27
JUNCTION
CONNECTORB A, J28J27
J UNCTION
CONNECTORB A, J28
II4 6
(
*1) (
*1)
A 22A 225A
STARTER
1J 3
B±W B±W
JUNCTION
CONNECTOR J29
C 14 C 15
C 15
BR
(
CALIFORNIA)
(
*1)
(
*2)
BR B B
E04
MRELNSW 2C 5
W±B