fog lights TOYOTA CAMRY 1994 XV10 / 4.G Wiring Diagrams Workshop Manual

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ENGINE CONTROL (5S±FE)
THIS SYSTEM UTILIZES AN ENGINE CONTROL MODULE (ENGINE ECU (M/T), ENGINE AND ELECTRONIC CONTROLLED
TRANSMISSION ECU (A/T)) 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. (WATER TEMP.) SIGNAL SYSTEM
THE ENGINE COOLANT TEMP. SENSOR (EFI WATER TEMP. SENSOR) DETECTS THE ENGINE COOLANT TEMP. AND HAS A
BUILT±IN THERMISTOR WITH A RESISTANCE WHICH VARIES ACCORDING TO THE ENGINE COOLANT TEMP. (WATER TEMP.)
THUS THE ENGINE COOLANT TEMP. (WATER TEMP.) IS INPUT IN THE FORM OF A CONTROL SIGNAL TO TERMINAL THW OF
THE ENGINE CONTROL MODULE (ECU).
(2) INTAKE AIR TEMP. SIGNAL SYSTEM
THE INTAKE AIR TEMP. SENSOR (IN±AIR TEMP. SENSOR) IS DETECTS THE INTAKE AIR TEMP., WHICH IS INPUT AS A
CONTROL SIGNAL TO TERMINAL THA OF THE ENGINE CONTROL MODULE (ECU).
(3) OXYGEN SENSOR SIGNAL SYSTEM
THE OXYGEN DENSITY IN THE EXHAUST GASES IS DETECTED AND INPUT AS A CONTROL SIGNAL TO TERMINAL OX1 AND
OX2 OF THE ENGINE CONTROL MODULE (ECU).
(4) RPM SIGNAL SYSTEM
CRANKSHAFT POSITION AND ENGINE RPM ARE DETECTED BY THE PICK±UP COIL INSTALLED INSIDE THE DISTRIBUTOR.
CRANKSHAFT POSITION IS INPUT AS A CONTROL SIGNAL TO TERMINALS G+ AND G2 (CALIFORNIA), OF THE ENGINE
CONTROL MODULE (ECU), AND RPM IS INPUT TO TERMINAL NE+.
(5) THROTTLE SIGNAL SYSTEM
THE THROTTLE POSITION SENSOR DETECTS THE THROTTLE VALVE OPENING ANGLE, WHICH IS INPUT AS A CONTROL
SIGNAL TO TERMINAL VTA OF THE ENGINE CONTROL MODULE (ECU), OR WHEN THE VALVE IS FULLY CLOSED, TO
TERMINAL IDL
(6) VEHICLE SPEED SIGNAL SYSTEM
THE VEHICLE SPEED SENSOR (SPEED SENSOR), INSTALLED INSIDE THE COMBINATION METER, DETECTS THE VEHICLE
SPEED AND INPUTS A CONTROL SIGNAL TO TERMINAL SPD OF THE ENGINE CONTROL MODULE (ECU).
(7) PARK/NEUTRAL POSITION SW (NEUTRAL START SW) SIGNAL SYSTEM (A/T)
THE PARK/NEUTRAL POSITION SW (NEUTRAL START SW) DETECTS WHETHER THE SHIFT POSITION ARE IN NEUTRAL AND
PARKING OR NOT, AND INPUTS A CONTROL SIGNAL TO TERMINAL NSW OF THE ENGINE CONTROL MODULE (ECU).
(8) A/C SW SIGNAL SYSTEM
THE A/C AMPLIFIER INPUTS THE A/C OPERATIONS TO TARMINAL ACA OF THE ENGINE CONTROL MODULE (ECU) AS A
CONTROL SIGNAL.
(9) BATTERY SIGNAL CIRCUIT
VOLTAGE IS CONSTANTLY APPLIED TO TERMINAL BATT OF THE ENGINE CONTROL MODULE (ECU). WHEN THE IGNITION SW
TURNED ON, THE VOLTAGE FOR ENGINE CONTROL MODULE (ECU) START±UP POWER SUPPLY IS APPLIED TO TERMINALS
+B AND +B1 OF ENGINE CONTROL MODULE (ECU) VIA EFI MAIN RELAY. THE CURRENT FLOWING THROUGH THE IGN FUSE
FLOWS TO TERMINAL IGSW OF THE ENGINE CONTROL MODULE (ECU).
(10) INTAKE AIR VOLUME SIGNAL SYSTEM
INTAKE AIR VOLUME IS DETECTED BY THE MANIFOLD ABSOLUTE PRESSURE SENSOR (VACUUM SENSOR) (FOR MANIFOLD
PRESSURE) AND IS INPUT AS A CONTROL SIGNAL TO TERMINAL PIM OF THE ENGINE CONTROL MODULE (ECU).
(11) STA 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 STA OF THE ENGINE CONTROL MODULE (ECU) AS A CONTROL
SIGNAL.
(12) ENGINE KNOCK SIGNAL CIRCUIT
ENGINE KNOCKING IS DETECTED BY KNOCK SENSOR AND THE SIGNAL IS INPUT INTO TERMINAL KNK AS A CONTROL
SIGNAL.
(13) ELECTRICAL LOAD SIGNAL SYSTEM
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.
SYSTEM OUTLINE