ac idle up TOYOTA CAMRY 1994 XV10 / 4.G Wiring Diagrams Workshop Manual

15
ABBREVIATIONS
ABBREVIATIONS
The following abbreviations are used in this manual.
ABS = Anti±Lock Brake System
ACIS = Acoustic Control Induction System
A/C = Air Conditioning
A/T = Automatic Transmission
COMB. = Combination
C/P = Coupe
ECU = Electronic Control Unit
EFI = Electronic Fuel Injection
EGR = Exhaust Gas Recirculation
ESA = Electronic Spark Advance
Ex. = Except
FL = Fusible Link
IAC = Idle Air Control
ISC = Idle Speed Control
J/B = Junction Block
LH = Left-Hand
MFI = Multiport Fuel Injection
M/T = Manual Transmission
O/D = Overdrive
R/B = Relay Block
RH = Right±Hand
RPM = Engine Speed
S/D = Sedan
SFI = Sequential Multiport Fuel Injection
SRS = Supplemental Restraint System
SW = Switch
TEMP. = Temperature
VSV = Vacuum Switching Valve
W/G = Wagon
w/ = With
w/o = Without
*The titles given inside the components are the names of the terminals (terminal codes) and
are not treated as being abbreviations.

29
Position of Parts in Engine Compartment
[1MZ±FE]
I 1 Idle Air Control Valve (ISC Valve) N 1 Noise Filter (for Ignition System)
I 2 Igniter
I 4 Injector No. 1 O 1 Oil Pressure SW
I 5 Injector No. 2 O 6 O/D Direct Clutch Speed Sensor
I 6 Injector No. 3
I 7 Injector No. 4 P 1 Park/Neutral Position SW (Neutral Start SW) (A/T)
I 8 Injector No. 5
I 9 Injector No. 6 S 1 Solenoid Valve (for Hydrauric Motor)
I 15 Igniter S 3 Starter
I 16 Ignition Coil No. 1 S 4Starter
I 17 Ignition Coil No. 2
I 18 Ignition Coil No. 3 T 1 Throttle Position Sensor
I 19 Ignition Coil No. 4
I 20 Ignition Coil No. 5 V 1 VSV (for A/C Idle±Up)
I 21 Ignition Coil No. 6 V 2 VSV (for EGR System)
V 3 VSV (for Fuel Pressure Up)
J 6 Junction Connector V 4 VSV (for Intake Air Control)
V 5 Vehicle Speed Sensor (Speed Sensor)
K 1 Knock Sensor 1
K 2 Knock Sensor 2 W 1 Washer Motor
W 2 Water Temp. Sender
M 6 Mass Air Flow (Air Flow Meter)

31
Position of Parts in Engine Compartment
[5S±FE]
H 1 Headlight Hi LH O 1 Oil Pressure SW
H 2 Headlight Hi RH O 2 Oxygen Sensor (Sub)
H 3 Headlight Lo LH O 3 Oxygen Sensor (Main)
H 4 Headlight Lo RH
H 5 Horn LH P 1 Park/Neutral Position SW (Neutral Start SW) (A/T)
H 6 Horn RH
R 1 Radiator Fan Motor
I 1 Idle Air Control Valve (ISC Valve)
I 2 Igniter S 3 Starter
I 3 Ignition Coil S 4Starter
I 4 Injector No. 1
I 5 Injector No. 2 T 1 Throttle Position Sensor
I 6 Injector No. 3
I 7 Injector No. 4 V 1 VSV (for A/C Idle±Up)
I 10 Intake Air Temp. Sensor (In±Air Temp. Sensor) V 2 VSV (for EGR System)
V 3 VSV (for Fuel Pressure Up)
K 1 Knock Sensor V 5 Vehicle Speed Sensor (Speed Sensor)
M 1 Manifold Absolute Pressure Sensor (Vacuum Sensor) W 1 Washer Motor
W 2 Water Temp. Sender
N 1 Noise Filter (for Ignition System)

32
ELECTRICAL WIRING ROUTING
Position of Parts in Instrument Panel
A 10 A/C Amplifier C 12 Combination SW
A 11 A/C Evaporator Temp. Sensor C 13 Combination SW
A 12 A/C SW C 14 Cooling Fan ECU
A 13 ABS ECU C 15 Cruise Control Clutch SW (M/T)
A 14 ABS ECU C 16 Cruise Control ECU
A 15 Airbag Squib (Steering Wheel Pad)
A 16 Air Inlet Control Servo Motor D 3 Data Lik Connector 2 (TDCL (Toyota Diagnostic
A 17 Air Vent Mode Control Servo Motor Communication Link))
A 18 Ashtray Illumination D 4 Daytime Running Light Relay (Main)
A 22 Airbag Squib (Front Passenger Airbag Assembly) D 5 Diode (for Cruise Control)
D 6 Diode (for Idle±Up)
B 3 Back Door Lock Control SW D 7 Diode (for Courtesy)
B 4 Blower Motor D 8 Door Lock Control Relay)
B 5 Blower Resistor D 24 Date Link Connector 3
B 6 Blower SW D 25 Diode (for Tension Reducer)
B 7 Buckle SW LH (w/ Power Seat)
B 8 Buckle SW LH (w/o Power Seat) E 6 Electronic Controlled Transmission Pattern Select SW
B 10 Buckle SW RH E 7 Engine Control Module (Engine and Electronic
Controlled Transmission ECU) (A/T)
C 3 Center Airbag Sensor Assembly E 8 Engine Control Module (Engine and Electronic
C 4 Cigarette Lighter Controlled Transmission ECU) (A/T)
C 5 Cigarette Lighter Illumination E 9 Engine Control Module (Engine and Electronic
C 6 ClockControlled Transmission ECU) (A/T)
C 7 Clutch Start SW (M/T) E 10 Engine Control Module (Engine and Electronic
C 8 Combination Meter Controlled Transmission ECU) (A/T)
C 9 Combination Meter E 11 Engine Control Module (Engine ECU) (M/T)
C 10 Combination Meter E 12 Engine Control Module (Engine ECU) (M/T)
C 11 Combination Meter E 14 Engine Control Module (Engine ECU) (M/T)

55
192 17711 4
11 8
Cruise Control Actuator
C2 C5 C10 C11 C13 D8C12 C3 C4 C6 C8 C9 C14 C16 D1 D3 D4 D6 D7
Center Airbag Sensor Assembly
Cigarette Lighter
Cigarette Lighter Illumination
Clock
Combination Meter
(Turn Signal Indicator Light)Combination Meter
(Cruise Control Indicator Light)
Combination Meter
Combination Meter
(Meter Illmination)
Combination Meter
(Open Door Warning Light)
Combination Meter
(Seat Belt Warning Light)
Combination Meter
(Charge Warning Light)
Combination Meter
(High Beam Indicator Light)
Combination Meter
(Rear Light Warning Light)
Combination Meter
Combination Meter
(SRS Warning Light)
Combination Meter
(A/T Indicator Light)
Combination SW (Horn SW)
Combination SW
(Turn Signal SW)
Combination SW
(Light Control SW)
Combination SW
Front Wiper and Washer SW)
Cooling Fan ECU (1MZ±FE)
Cruise Control ECU
Data Link Connector 1
(Check Connector)
Data Link Connector 2
(TDCL (Toyota Diagnostic
Communication Link))
Daytime Running Light Relay
(Main) (CANADA)
Diode (for Idle±Up)
Diode (for Courtesy) (W/G) Door Lock Control Relay
18912618968
72192236210
21476 130
134
138
140 126120
124
144
148236126
198
204104
11 2
144244 80
90
98
214 90
192
214106
23680
90
98130
134
138
140156
140 104
106
D9 C717080
90
98177 17311 4
11 8106
126
148184
186192 98
204134
140
Diode (for Courtesy) Combination Meter
(Malfunction Indicator Light) Combination Meter
(ABS Warning Light) Clutch Start SW (M/T)
(4): R/B No. 4 (See page 20)(5): R/B No. 5 (See page 19)(6)R/B No. 6 (See Page )
2526 26

57
E10 80
98
204 80
90
98
236 184
F376 144
148126
246252
Engine Control Module (Engine
and Electronic Controlled
Transmission ECU)
High Mount Stop Light
Heated Oxygen Sensor (Bank 2
Sensor 1) (1MZ±FE)
Idle Air Control Valve (ISC Valve)
Igniter
Ignition Coil
Injector No. 1
F4 F5 F6 F7 F8 F9 F15 G2 G3 G4 H1 H2 H3 H4 H5 H6 H7 H8 H9 H10 H11 H12 I1 I2 I3 I4 90
198144
148144
148144
14811 4
11 811 4
11 8126 126 104 106 104 106 104 106 104 106 173 17311 4
11 8
12680120
12480 8080
90
9868
8072
98
23672 80
Heated Oxygen Sensor (Bank 1
Sensor 1) (1MZ±FE) Heated Oxygen Sensor (Bank 1
Sensor 2) Air Vent Mode Control SW (for
Lever Control SW Type) Heater Control SW (for Push
Control SW Type) Hazard SW Horn RH
Horn LH Front Clearance Light LH
Front Clearance Light RH
Front Side Marker LH
Front Side Marker RH
Front turn Signal Light LH
Front turn Signal Light RH
Front Wiper Motor
Fuel Pump and Sender
Generator (Alternator)
Glove Box Light
Glove Box Light SW
Headlight Hi LH (USA)
Headlight Hi LH (CANADA)
Headlight Hi RH (USA)
Headlight Hi RH (CANADA)
Headlight Lo LH (USA)
Headlight Lo LH (CANADA)
Headlight Lo RH (USA)
Headlight Lo RH (CANADA)
(4): R/B No. 4 (See page 20)(5): R/B No. 5 (See page 19)(6)R/B No. 6 (See Page )
2526 26

61
186
R18 R19 R20 R21 S3 S8 S9 S10 V1 V2 V3 V468
72182226
23080
90
98
Rear Wiper Motor (W/G)
Rear Wiper Relay (W/G)
Remote Control Mirror LH
Remote Control Mirror RH
Shift Lock ECU
Stereo Component Amplifier
Stereo Component Amplifier
Stop Light SW
VSV (for A/C Idle±Up)
VSV (for EGR System) (1MZ±FE)
VSV (for Fuel Pressure Up)
VSV (for Intake Air Control)
(1MZ±FE)
Vehicle Speed Sensor
(Speed Sensor)
Vanity Light LH
Vanity Light RH
Washer Motor
Water Temp. Sender
Diode
Noise Filter
Defogger Relay (Coil Side)
Power Main Relay (Coil Side)
S5 V5 V8 V9 W1 W2
Starter (1MZ±FE)
Defogger Relay (Point Side)
Power Main Relay (Point Side)
Taillight Relay (Coil Side)
Taillight Relay (Point Side)
Starter Relay (Point Side)
Starter Relay (Coil Side)
EFI Main Relay (Coil Side)
EFI Main Relay (Point Side)
Headlight Relay (Coil Side)
186 154 154226
230120
192
204182
198
210
21480
9080
90
9880 80
98
198 90
192
236130
134
138130
134
138184
186236130
134
138190 190 190156
160
168156
160
16811 2
12612668
7268
72 80
90
98
198
204 80
90
98
198
204106
(4): R/B No. 4 (See page 20)(5): R/B No. 5 (See page 19)(6)R/B No. 6 (See Page )
2526 26

79
2. CONTROL SYSTEM
*SFI (SEQUENTIAL MULTIPORT FUEL INJECTION) (EFI (ELECTRONIC FUEL INJECTION) SYSTEM
THE EFI SYSTEM MONITORS THE ENGINE CONDITION THROUGH THE SIGNALS INPUT FROM EACH SENSOR (INPUT SIGNALS
FROM (1) TO (12) ETC.). THE BEST FUEL INJECTION VOLUME IS DECIDED BASED ON THIS DATA AND THE PROGRAM MEMORIZED
BY THE ENGINE CONTROL MODULE (ECU), AND THE CONTROL SIGNAL IS OUTPUT TO TERMINALS #10, #20, #30, #40, #50 AND #60
OF THE ENGINE CONTROL MODULE (ECU) TO OPERATE THE INJECTOR (INJECT THE FUEL). THE EFI SYSTEM PRODUCES
CONTROL OF FUEL INJECTION OPERATION BY THE ENGINE CONTROL MODULE (ECU) IN RESPONSE TO THE DRIVING
CONDITIONS.
*ESA (ELECTRONIC SPARK ADVANCE) SYSTEM
THE ESA SYSTEM MONITORS THE ENGINE CONDITION THROUGH THE SIGNALS INPUT TO THE ENGINE CONTROL MODULE (ECU)
FROM EACH SENSOR (INPUT SIGNALS FROM (1), (3), (4) TO (12) ETC.). THE BEST IGNITION TIMING IS DECIDED ACCORDING TO
THIS DATA AND THE MEMORIZED DATA IN THE ENGINE CONTROL MODULE (ECU) AND THE CONTROL SIGNAL IS OUTPUTS TO
TERMINALS IGT1, IGT2, IGT3, IGT4, IGT5 AND IGT6. THIS SIGNAL CONTROLS THE IGNITER TO PROVIDE THE BEST IGNITION
TIMING FOR THE DRIVING CONDITIONS.
*HEATED OXYGEN SENSOR (OXYGEN SENSOR) HEATER CONTROL SYSTEM
THE OXYGEN SENSOR HEATER CONTROL SYSTEM TURNS THE HEATER ON WHEN THE INTAKE AIR VOLUME IS LOW (TEMP. OF
EXHAUST EMISSIONS IS LOW), AND WARMS UP THE OXYGEN SENSOR (NO. 1 AND NO. 2) TO IMPROVE DETECTION
PERFORMANCE OF THE SENSOR.
THE ENGINE CONTROL MODULE (ECU) EVALUATES THE SIGNALS FROM EACH SENSOR (INPUT SIGNALS FROM (1), (4), (9) TO (10)
ETC.), AND OUTPUT CURRENT TO TERMINALS HTL, HTR AND HTS AND CONTROL THE HEATER.
*IAC (IDLE AIR CONTROL (ISC)) SYSTEM
THE IAC (ISC) SYSTEM (ROTARY SOLENOID TYPE) INCREASES THE RPM AND PROVIDES IDLE STABILITY FOR FAST IDLE±UP
WHEN THE ENGINE IS COLD, AND WHEN THE IDLE SPEED HAS DROPPED DUE TO ELECTRICAL LOAD AND SO ON, THE ENGINE
CONTROL MODULE (ECU) EVALUATES THE SIGNALS FROM EACH SENSOR (INPUT SIGNALS FROM (1), (4), (5), (8), (9) ETC.),
OUTPUTS CURRENT TO TERMINALS RSO AND RSC TO CONTROL IDLE AIR CONTROL VALVE.
*EGR CONTROL SYSTEM
THE EGR CONTROL SYSTEM DETECTS THE SIGNAL FROM EACH SENSOR (INPUT SIGNALS FROM (1), (4), (9), (10), ETC)., AND
OUTPUTS CURRENT TO TERMINAL EGR TO CONTROL THE EGR VALVE.
*ACIS (ACOUSTIC CONTROL INDUCTION SYSTEM)
ACIS INCLUDES A VALVE IN THE BULKHEAD SEPARATING THE SURGE TANK INTO TWO PARTS. THIS VALVE IS OPENED AND
CLOSED IN ACCORDANCE WITH THE DRIVING CONDITIONS TO CONTROL THE INTAKE MANIFOLD LENGTH IN TWO STAGES FOR
INCREASED ENGINE OUTPUT IN ALL RANGES FROM LOW TO HIGH SPEEDS.
THE ENGINE CONTROL MODULE (ECU) JUDGES THE ENGINE SPEED BY THE SIGNALS ((4), (5)) FROM EACH SENSOR AND
OUTPUTS SIGNALS TO THE TERMINAL ACIS TO CONTROL THE VSV (FOR OPENING AND CLOSING THE INTAKE CONTROL VALVE)
3. DIAGNOSIS SYSTEM
WITH THE DIAGNOSIS SYSTEM, WHEN THERE IS A MALFUNCTION IN THE ENGINE CONTROL MODULE (ECU) SIGNAL SYSTEM, THE
MALFUNCTIONING SYSTEM IS RECORDED IN THE MEMORY.
4. FAIL±SAFE SYSTEM
WHEN A MALFUNCTION HAS OCCURRED 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 (ECU) MEMORY OR ELSE STOPS THE
ENGINE.

81
A
M 45
BL EBBX15 D 14
BATT
D 21
ELSA 14
NSWA 13
STA
D 23+B
D 22+B1
A 9#20
A 6#50
A 7#40
A 8#30
A 5#60
A 10#10 2B 22C32D4
IP3 12 I18
I23
L± B
G±R
Y
R
L
GR
G
W B± O B± OL± B B±W
B±WB± O
L±B B±O
B±O
B±O
G±R
W± B
B±O
W±G W±L
B±R
B±W
B±W B±OB±O B±O
W±BB±O
B±O
Y
R
L
GR
G
W
W±B F15
FUEL PUMPENGINE CONTROL MODULE
(
ENGINE AND ELECTRONIC
CONTROLLED TRANSMISSION ECU) 25 13
E7 , E8 ,E9 , E10 D
BC
IP120
B±W
I23
L±B 15A
EFIFROM POWE
G G
P
2 3
1 2D 2 IP1 18
DIODE
(
FOR IDLE±UP) D6
B±O
W±BB±O
B±O
EF1 1
IP3 18
B±W
B±WB±O
I18 E10 E12 E11
1 2
2 1
2 1
2 1
2 1
3
A 23
RSOA 22
RSCC 1
ACVC 12
EGRA 25
FPUC 6
ACIS AA A
B± O B±O
B±O
B±O
B±O
B±O G±B
Y± B
W±L
B±L
B±R
R±Y
JUNCTION
CONNECTOR J6 B±O B±O
B±O B±O B±O
ILDE AIR CONTROL VALVE
(
ISC VALVE)
VSV
(
FOR A/C IDLE±UP)
VSV
(
FOR EGR)
VSV
(
FOR FUEL PRESSURE UP)
VSV
(
FOR INTAKE AIR CONTROL) I1
V1
V2
V3
V4EFI MAIN
RELAY
IP111
1G 6
1E 5 1DA
MIR±
HTR
1A 14 10
3C 53D 5TA I L
R SOURCE SYSTEM(
SEE PAGE 64)
10
15A

89
2. CONTROL SYSTEM
*MFI (MULTIPORT FUEL INJECTION (EFI)) SYSTEM
THE MFI (EFI) SYSTEM MONITORS THE ENGINE CONDITION THROUGH THE SIGNALS INPUT FROM EACH SENSOR (INPUT
SIGNALS FROM (1) TO (13) ETC.) TO THE ENGINE CONTROL MODULE (ECU). THE BEST FUEL INJECTION VOLUME IS DECIDED
BASED ON THIS DATA AND THE PROGRAM MEMORIZED BY THE ENGINE CONTROL MODULE (ECU), AND THE CONTROL SIGNAL
IS OUTPUT TO TERMINALS #10, #20, #30 AND #40 (CALIFORNIA), TERMINALS #10 AND #20 (EX. CALIFORNIA) OF THE ENGINE
CONTROL MODULE (ECU) TO OPERATE THE INJECTOR. (INJECT THE FUEL). THE MFI (EFI) SYSTEM PRODUCES CONTROL OF
FUEL INJECTION OPERATION BY THE ENGINE CONTROL MODULE (ECU) IN RESPONSE TO THE DRIVING CONDITIONS.
*ESA (ELECTRONIC SPARK ADVANCE) SYSTEM
THE ESA SYSTEM MONITORS THE ENGINE CONDITION THROUGH THE SIGNALS INPUT TO THE ENGINE CONTROL MODULE (ECU)
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 (ECU) AND THE CONTROL SIGNAL IS OUTPUT TO
TERMINAL IGT. THIS SIGNAL CONTROLS THE IGNITER TO PROVIDE THE BEST IGNITION TIMING FOR THE DRIVING CONDITIONS.
*IAC (IDLE AIR CONTROL (ISC)) SYSTEM
THE IAC (ISC) SYSTEM (ROTARY SOLENOID 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 (ECU) 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 (ISC VALVE).
*FUEL PUMP CONTROL SYSTEM
THE ENGINE CONTROL MODULE (ECU) OPERATION OUTPUTS TO TERMINAL FC AND CONTROLS THE CIRCUIT OPENING RELAY
AND THUS CONTROLS THE FUEL PUMP DRIVE SPEED IN RESPONSE TO CONDITIONS.
*A/C IDLE±UP SYSTEM
IN ORDER TO PREVENT THE ENGINE IDLING SPEED FROM DROPPING WHEN THE A/C IS OPERATING, THE A/C IDLE±UP SYSTEM
CONTROLS THE VSV (FOR A/C IDLE±UP) TO INCREASE THE ENGINE IDLING SPEED AND KEEP IT STABLE.
*EGR CONTROL SYSTEM
THE EGR CUT CONTROL SYSTEM CONTROLS THE VSV (FOR EGR) BY EVALUATING THE SIGNALS FROM EACH SENSOR INPUT TO
THE ENGINE CONTROL MODULE (ECU) (INPUT SIGNALS (1), (5), (6), (9) ETC.) AND BY SENDING OUTPUT TO TERMINAL THG OF
THE ENGINE CONTROL MODULE (ECU).
*A/C CUT CONTROL SYSTEM
WHEN THE VEHICLE SUDDENLY ACCELERATES FROM LOW ENGINE SPEED, THIS SYSTEM CUTS OFF AIR CONDITIONING
OPERATION FOR A FIXED PERIOD OF TIME IN RESPONSE TO THE VEHICLE SPEED AND THROTTLE VALVE OPENING ANGLE IN
ORDER TO MAINTAIN ACCELERATION PERFORMANCE.
THE ENGINE CONTROL MODULE (ECU) RECEIVES INPUT SIGNALS ((5), (6) ETC.), AND OUTPUTS SIGNALS TO TERMINAL ACT.
3. DIAGNOSIS SYSTEM
WITH THE DIAGNOSIS SYSTEM, WHEN THERE IS A MALFUNCTIONING IN THE ENGINE CONTROL MODULE (ECU) 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 (CHECK ENGINE WARNING LIGHT).
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 (ECU) MEMORY OR ELSE STOPS THE
ENGINE.