fuel type TOYOTA CAMRY 1994 XV10 / 4.G Wiring Diagrams Workshop Manual

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

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.

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.