Toyota MCV10 Automobile User Manual


 
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ENGINE CONTROL (1MZ–FE)
THIS SYSTEM UTILIZES AN ENGINE CONTROL MODULE (ENGINE AND ELECTRONIC CONTROLLED TRANSMISSION ECU) 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 CIRCUIT
THE ENGINE COOLANT TEMP. SENSOR (WATER 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 ENGINE CONTROL MODULE (ECU) AS A CONTROL SIGNAL.
(2) INTAKE AIR TEMP. SIGNAL CIRCUIT
THE INTAKE AIR TEMP. SENSOR IS INSTALLED IN THE MASS AIR FLOW (AIR FLOW METER) AND DETECTS THE INTAKE AIR
TEMP., WHICH IS INPUT AS A CONTROL SIGNAL TO TERMINAL THA OF 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 OXL, OXR
AND OXS OF THE ENGINE CONTROL MODULE (ECU). TO MAINTAIN STABLE DETECTION PERFORMANCE BY THE OXYGEN
SENSOR, A HEATER IS USED FOR WARMING THE SENSOR. THE HEATER IS ALSO CONTROLLED BY THE ENGINE CONTROL
MODULE (ECU) (HTL, HTR AND HTS).
(4) RPM SIGNAL SYSTEM
CAMSHAFT POSITION AND CRANKSHAFT POSITION ARE DETECTED BY THE CAMSHAFT POSITION SENSOR AND
CRANKSHAFT POSITION SENSOR. CRANKSHAFT POSITION IS INPUT AS A CONTROL SIGNAL TO TERMINAL G22+ OF THE
ENGINE CONTROL MODULE (ECU), AND ENGINE RPM IS INPUT TO 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 VTA OF THE ENGINE CONTROL MODULE (ECU). WHEN THE VALVE IS COMPLETELY CLOSED, THE
CONTROL SIGNAL IS INPUT INTO 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 SP1 OF THE ENGINE CONTROL MODULE (ECU).
(7) PARK/NEUTRAL POSITION SW (NEUTRAL START SW) SIGNAL SYSTEM
THE PARK/NEUTRAL POSITION SW (NEUTRAL START SW) DETECTS WHETHER THE SHIFT POSITION IS IN NEUTRAL OR
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 TEMRINAL A/C 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, 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.
(10) INTAKE AIR VOLUME SIGNAL CIRCUIT
INTAKE AIR VOLUME IS DETECTED BY THE MASS AIR FLOW (AIR FLOW METER) AND THE SIGNAL IS INPUT TO TERMINAL VG
OF THE ENGINE CONTROL MODULE (ECU). AS A CONTROL SIGNAL.
(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 THE KNOCK SENSOR NO. 1 AND NO. 2 AND THE SIGNALS ARE INPUT INTO TERMINALS
KNKR AND KNKL AS A CONTROL SIGNAL.
SYSTEM OUTLINE