SYSTEMEC-49
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The ECM receives information such as the injecti
on pulse width and camshaft position sensor (PHASE) sig-
nal. Computing this information, ignition si gnals are transmitted to the power transistor.
During the following conditions, the ignition timing is revi sed by the ECM according to the other data stored in
the ECM.
• At starting
• During warm-up
•At idle
• At low battery voltage
• During acceleration
The knock sensor retard system is designed only for emergencies. The basic ignition timing is programmed
within the anti-knocking zone, if recommended fuel is used under dry conditions. The retard system does not
operate under normal driving conditions. If engine knocking occurs, the knock sensor monitors the condition.
The signal is transmitted to the ECM. The ECM retards the ignition timing to eliminate the knocking condition.
INTAKE VALVE TIMING CONTROL
INTAKE VALVE TIMING CONTROL : System DescriptionINFOID:0000000009462096
INTAKE VALVE TIMING CONTROL
System Diagram
Input/Output Signal Chart
*: This signal is sent to the ECM through CAN communication line
JPBIA4760GB
Sensor Input signal to ECM ECM function Actuator
Crankshaft position sensor (POS) Engine speed and piston position
Intake valve
timing control Intake valve timing control
solenoid valve
Camshaft position sensor (PHASE)
Engine oil temperature sensor Engine oil temperature
Engine coolant temperature sensor Engine coolant temperature
Combination meter Vehicle speed*
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SYSTEMEC-51
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The intake valve timing intermediate lock control improv
es the cleaning ability of exhaust gas at cold starting
by fixing the camshaft sprocket (INT) with two lock keys and bringing the cam phase into intermediate phase.
Cam phase is fixed at the intermediate phase by two lock keys in the camshaft sprocket (INT). Lock key 1 con-
trols retard position and lock key 2 controls advance position.
ECM controls the intermediate phase lock by opening/clos ing the intake valve timing intermediate lock control
solenoid valve to control oil pressure acti ng on the lock key and locking/unlocking the lock key.
Lock/Unlock Activation
When ECM activates the intake valve timing intermediate lock control solenoid valve, oil pressure generated in
the oil pump is drained through the oil pressure path in t he control valve. Since oil pressure is not acted on the
lock key, the lock key position is fixed by the spri ng tension and the cam phase is fixed at the intermediate
phase.
When ECM deactivates the intake valve timing intermediate lock control solenoid valve, unlocking oil pressure
acts on each lock key. Lock key 1 is not released because it is under load due to sprocket rotational force. For
this reason, lock key 2 is released first by being pushed up by unlocking oil pressure. When lock key 2 is
released, some clearance is formed between lock key 1 and the rotor due to sprocket rotational force and
return spring force. Accordingly, lock key 1 is pushed up by unlocking oil pressure and the intermediated
phase lock is released.
When stopping the engine
When the ignition switch is turned from idle state to OFF, ECM receives an ignition switch signal from BCM via
CAN communication and activates the intake valve timing intermediate lock control solenoid valve and drains
oil pressure acting on the lock key before activating the intake valve timing control solenoid valve and operat-
ing the cam phase toward the advance position.
The cam phase is fixed by the lock key when shifting to the intermediated phase and ECM performs Lock
judgment to stop the engine.
When starting the engine
JPBIA6317GB
JPBIA5970GB
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EC-52
< SYSTEM DESCRIPTION >[QR25DE]
SYSTEM
When starting the engine by cold start, ECM judges the
locked/unlocked state when ignition switch is turned
ON. When judged as locked state (fixed at the intermedi ate phase), the intake valve timing intermediate lock
control solenoid valve is activated. Since oil pre ssure does not act on the lock key even when the engine is
started, the cam phase is fixed at the intermediate phas e and the intake valve timing control is not performed.
When the engine stops without locking the cam phase at the intermediate phase due to an engine stall and the
state is not judged as locked, the intake valve timing intermediate lock control solenoid valve and the intake
valve timing control solenoid valve are activated and the cam phase shifts to the advanced position to be
locked at the intermediate phase. Even when not locked in the intermediate lock phase due to no oil pressure
or low oil pressure, a ratchet structure of the camshaft sprocket (INT) rotor allows the conversion to the inter-
mediate phase in stages by engine vibration.
When engine coolant temperature is more than 60 °C, the intake valve timing is controlled by deactivating the
intake valve timing intermediate lock control so lenoid valve and releasing the intermediate phase lock.
When the engine is started after warming up, ECM releas es the intermediate phase lock immediately after the
engine start and controls the intake valve timing.
EXHAUST VALVE TIMING CONTROL
EXHAUST VALVE TIMING CONT ROL : System DescriptionINFOID:0000000009462097
SYSTEM DIAGRAM
INPUT/OUTPUT SIGNAL CHART
JPBIA4761GB
Sensor Input signal to ECM ECM function Actuator
Crankshaft position sensor (POS) Engine speed and piston position
Exhaust valve
timing control Exhaust valve timing control
solenoid valve
Camshaft position sensor (PHASE)
Engine oil temperature sensor Engine oil temperature
Exhaust valve timing control position
sensor Exhaust valve timing signal
Combination meter CAN commu-
nication Vehicle speed signal
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SYSTEMEC-53
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SYSTEM DESCRIPTION
This mechanism hydraulically controls cam phases c
ontinuously with the fixed operating angle of the exhaust
valve.
The ECM receives signals such as crankshaft position, camshaft position, engine speed, and engine oil tem-
perature. Then, the ECM sends ON/OFF pulse duty signal s to the exhaust valve timing (EVT) control solenoid
valve depending on driving status. This makes it possible to control the shut/open timing of the exhaust valve
to increase engine torque and output in a range of high engine speed.
INTAKE MANIFOLD RUNNER CONTROL
INTAKE MANIFOLD RUNNER CONTROL : System DescriptionINFOID:0000000009462098
SYSTEM DIAGRAM
SYSTEM DESCRIPTION
Intake manifold runner control valve has a valve portion in the intake passage of each cylinder.
While idling and during low engine coolant temperature, t he intake manifold runner control valve closes. Thus
the velocity of the air in the intake passage increases , promoting the vaporization of the fuel and producing a
intake manifold runner in the combustion chamber.
Because of this operation, this system tends to in crease the burning speed of the gas mixture, improve
exhaust emission, and increase the stability in running conditions.
JPBIA5972GB
JPBIA6226GB
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SYSTEMEC-55
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Intake Manifold Tuning Valve Operating Condition
ECM opens the intake manifold tuning valve when all of the following conditions are satisfied.
• Engine speed: 5,000 rpm or more
• Engine coolant temperature: -30 °C (-22 °F) or more
• Battery voltage: 16 V or less
ENGINE PROTECTION CONTROL AT LOW ENGINE OIL PRESSURE
ENGINE PROTECTION CONTROL AT LOW ENGINE OIL PRESSURE : System De-
scription
INFOID:0000000009462100
SYSTEM DIAGRAM
INPUT/OUTPUT SIGNAL CHART
SYSTEM DESCRIPTION
• The engine protection control at low engine oil pressure warns the driver of a decrease in engine oil pres-
sure by the oil pressure warning lamp a before the engine becomes damaged.
• When detecting a decrease in engine oil pressure at an engine speed less than 1,000 rpm, ECM transmits an oil pressure warning lamp signal to the combination meter.The combination meter turns ON the oil pres-
sure warning lamp, according to the signal.
*: When detecting a normal engine oil pressure, ECM turns OFF the oil pressure warning lamp.
FUEL FILLER CAP WARNING SYSTEM
JPBIA4922GB
Sensor Input signal to ECM ECM function Actuator
Engine oil pressure sensor Engine pressure Engine protection control
• Oil pressure warning lamp
signal
•FUel cut control Combination meter
• Oil pressure warning lamp
Crankshaft position sensor
(POS) Engine speed
Engine oil temperature sensor Engine oil temperature
Decrease in engine oil pressure Engine speed Combination meter
Fuel cut
Oil pressure warning lamp
Detection Less than 1,000 rpm ON* NO
1,000 rpm or more ON YES
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EC-82
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DIAGNOSIS SYSTEM (ECM)
ALT DUTY SIG On/Off• The control condition of the power gener-
ation voltage variable control (deter-
mined by ECM according to the input
signals) is indicated.
- On: Power generation voltage variable control is active.
- Off: Power generation voltage variable control is inactive.
I/P PULLY SPD rpm • Indicates the engine speed computed
from the input speed sensor signal.
VEHICLE SPEED km/h or mph • The vehicle speed computed from the
vehicle speed signal sent from TCM is
displayed.
IDL A/V LEARN YET/CMPLT • Displays the condition of Idle Air Volume
Learning
- YET: Idle air volume learning has not been performed yet.
- CMPLT: Idle air volume learning has al-
ready been performed successfully.
TRVL AFTER MIL km or mile • Distance traveled while MIL is activated.
ENG OIL TEMP °C or °F • The engine oil temperature (determined
by the signal voltage of the engine oil
temperature sensor) is displayed.
A/F S1 HTR(B1) % • Air fuel ratio (A/F) sensor 1 heater control
value computed by ECM according to the
input signals.
• The current flow to the heater becomes
larger as the value increases.
VHCL SPEED SE km/h or mph • The vehicle speed computed from the
vehicle speed signal sent from combina-
tion meter is displayed.
SET VHCL SPD km/h or mph • The preset vehicle speed is displayed.
MAIN SW On/Off • Indicates [ON/OFF] condition from MAIN
switch signal.
CANCEL SW On/Off • Indicates [ON/OFF] condition from CAN-
CEL switch signal.
RESUME/ACC SW On/Off • Indicates [ON/OFF] condition from RE-
SUME/ACCELERATE switch signal.
SET SW On/Off • Indicates [ON/OFF] condition from SET/
COAST switch signal.
BRAKE SW1 On/Off • Indicates [ON/OFF] condition from brake
pedal position switch signal.
BRAKE SW2 On/Off • Indicates [ON/OFF] condition of stop
lamp switch signal.
VHCL SPD CUT Non/Cut • Indicates the vehicle cruise condition.
- Non: Vehicle speed is maintained at the
ASCD set speed.
- Cut: Vehicle speed decreased to exces- sively low compared with the ASCD set
speed, and ASCD operation is cut off.
Monitored item Unit
Monitor Item
Selection
Description Remarks
ECU
IN-
PUT
SIG-
NALS MAIN
SIG-
NAL S
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EC-86
< SYSTEM DESCRIPTION >[QR25DE]
DIAGNOSIS SYSTEM (ECM)
*: Leaving cooling fan OFF with CONSULT while engine is running may cause the engine to overheat.
DTC WORK SUPPORT MODE
DTC WORK SUPPORT Mode
ALTERNATOR
DUTY • Engine: Idle
• Change duty ratio using CON-
SULT. Battery voltage changes.
• Harness and connectors
•IPDM E/R
•Alternator
FUEL PUMP RELAY • Ignition switch: ON (Engine
stopped)
• Turn the fuel pump relay “ON”
and “OFF” using CONSULT and
listen to operating sound. Fuel pump relay makes the operat-
ing sound. • Harness and connectors
• Fuel pump relay
VIAS S/V-1 • Ignition switch: ON
• Turn intake manifold tuning valve
“ON” and “OFF” using CONSULT
and listen to operating sound. Intake manifold tuning valve motor
makes an operating sound. • Harness and connectors
• Intake manifold tuning valve mo- tor
TUMBLE CONTROL
VA LV E • Ignition switch: ON
• Turn intake manifold runner con-
trol valve “ON” and “OFF” using
CONSULT and listen to operating
sound. Intake Manifold Runner control
valve motor makes an operating
sound. • Harness and connectors
• Intake Manifold Runner control valve motor
IGNITION TIMING • Engine: Return to the original
trouble condition
• Timing light: Set
• Retard the ignition timing using
CONSULT. If trouble symptom disappears, see
CHECK ITEM. • Perform Idle Air Volume Learn-
ing.
POWER BALANCE • Engine: After warming up, idle the
engine.
• A/C switch OFF
• Selector lever: P or N
• Cut off each fuel injector signal one at a time using CONSULT. Engine runs rough or stops. • Harness and connectors
• Compression
• Fuel injector
• Power transistor
• Spark plug
• Ignition coil
VENT CONTROL/V • Ignition switch: ON (Engine
stopped)
• Turn solenoid valve “ON” and “OFF” using CONSULT and listen
to operating sound. Solenoid valve makes an operating
sound. • Harness and connectors
• Solenoid valve
INT V/T ASSIGN AN-
GLE • Engine: Return to the original
trouble condition
• Change intake valve timing using
CONSULT. If trouble symptom disappears, see
CHECK ITEM. • Harness and connectors
• Intake valve timing control sole- noid valve
EXH V/T ASSIGN
ANGLE • Engine: Return to the original
trouble condition
• Change exhaust valve timing us- ing CONSULT. If trouble symptom disappears, see
CHECK ITEM. • Harness and connectors
• Exhaust valve timing control so-
lenoid valve
COOLING FAN* • Ignition switch: ON
• Turn the cooling fan “LOW”, “HI” and “OFF” using CONSULT. Cooling fan moves and stops. • Harness and connectors
• IPDM E/R (Cooling fan relay)
• Cooling fan motor
Test item Condition Judgment Check item (Remedy)
Test mode Test item Corresponding DTC No. Reference page
EVAPORATIVE SYSTEM PURG FLOW P0441 P0441
EC-337
PURG VOL CN/V P1444 P0443EC-342
A/F SEN1 A/F SEN1(B1) P1276 P0130 EC-258
HO2S2HO2S2(B1) P1146 P0138
EC-274HO2S2(B1) P1147 P0137EC-268
HO2S2(B1) P0139 P0139EC-282
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EC-90
< ECU DIAGNOSIS INFORMATION >[QR25DE]
ECM
VIAS S/V-1• Engine: After warming up
• Selector lever: P or N
• Air conditioner switch: OFF
•No load When revving engine up to 5,000 rpm
quickly Off
→ On → Off
AIR COND RLY • Engine: After warming up, idle the
engine Air conditioner switch: OFF Off
Air conditioner switch: ON
(Compressor operates) On
FUEL PUMP RLY • For 1 second after turning ignition switch: ON
• Engine running or cranking On
• Except above Off
VENT CONT/V • Ignition switch: ON Off
THRTL RELAY • Ignition switch: ON On
COOLING FAN • Engine: After warming up, idle the
engine
• Air conditioner switch: OFF Engine coolant temperature is 97
°C
(207 °F) or less Off
Engine coolant temperature between
98 °C (208 °F) and 99 °C (210 °F) or more Low
Engine coolant temperature between
100 °C (212 °F) or more Hi
• Engine: After warming up, idle the engine
• Air conditioner switch: ON
• Refrigerant pressure is less than 1,280 kPa (12.80 bar, 13.05 kg/
cm
2, 185.6 psi) Engine coolant temperature is 97
°C
(207 °F) or less Off
Engine coolant temperature between
98 °C (208 °F) and 99 °C (210 °F) or more Mid
Engine coolant temperature between
100 °C (212 °F) or more Hi
HO2S2 HTR (B1) • Engine speed: Below 3,600 rpm after the following conditions are met.
- Engine: After warming up
- Keeping the engine speed between 3,500 and 4,000 rpm for 1 minute and at
idle for 1 minute under no load On
• Engine speed: Above 3,600 rpm Off
ALT DUTY SIG • Power generation voltage variable control: Operating On
• Power generation voltage variable control: Not operating Off
I/P PULLY SPD • Vehicle speed: More than 20 km/h (12 MPH) Almost the same speed as
the tachometer indication
VEHICLE SPEED • Turn drive wheels and compare CONSULT value with the speedometer indi-
cation. Almost the same speed as
the speedometer indication
IDL A/V LEARN • Engine: running Idle air volume learning has not been per-
formed yet. YET
Idle air volume learning has already been
performed successfully. CMPLT
TRVL AFTER MIL • Ignition switch: ON Vehicle has traveled after MIL has turned
ON. 0 - 65,535 km
(0 - 40,723 miles)
ENG OIL TEMP • Engine: After warming up More than 70 °C (158 °F)
A/F S1 HTR(B1) • Engine: After warming up, idle the engine
(More than 140 seconds after starting engine.) 4 - 100%
VHCL SPEED SE • Turn drive wheels and compare CONSULT value with the speedometer indi-
cation. Almost the same speed as
the speedometer indication
SET VHCL SPD • Engine: Running ASCD: Operating The preset vehicle speed is
displayed
MAIN SW • Ignition switch: ON MAIN switch: Pressed On
MAIN switch: Released Off
Monitor Item Condition Values/Status
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