A79052
A6
Mass Air Flow MeterECM
1
3 EVG
VG
L±Y
G
2
B±R 12
EA1 32
E12
24
E12
B±R
From
Terminal 2 of
EFI No.1 Fuse
(See Page 05±124)
±
DIAGNOSTICS SFI SYSTEM(1ZZ±FE/3ZZ±FE)
05±25
AVENSIS REPAIR MANUAL (RM1018E)
WIRING DIAGRAM
INSPECTION PROCEDURE
HINT:
Read freeze frame data using \f \b\f\f
Freeze frame data records the engine conditions when
a malfunction is detected. When troubleshooting, it is useful for determi\
ning whether the vehicle was running
or stopped, the engine was warmed up or not, the air±fuel ratio was lea\
n or rich, etc. at the time of the mal-
function.
1READ VALUE OF HAND±HELD TESTER(MASS AIR FLOW RATE)
(a)Connect the hand±held tester to the DLC3.
(b)Start the engine.
(c)Read air flow rate on the hand±held tester.
(d)Select the item ºDIAGNOSIS / OBD/MOBD / DATA LIST / ALL / MAFº and read its value displayed on the hand±held tester.
Result:
Air flow rate (gm/sec)Proceed to
0.0A
271.0 or moreB
1 less than Mass Air Flow Rate less than 270.0 or more (*1)C
*1: The value must be changed when the throttle valve is opend or closed.
BGo to step 6
CCHECK FOR INTERMITTENT PROBLEMS(See Page 05±5)
A
± DIAGNOSTICSSFI SYSTEM (1ZZ±FE/3ZZ±FE)
05±73
AVENSIS REPAIR MANUAL (RM1018E)
DTC P0300 RANDOM/MULTIPLE CYLINDER MISFIRE
DETECTED
DTC P0301 CYLINDER 1 MISFIRE DETECTED
DTC P0302 CYLINDER 2 MISFIRE DETECTED
DTC P0303 CYLINDER 3 MISFIRE DETECTED
DTC P0304 CYLINDER 4 MISFIRE DETECTED
CIRCUIT DESCRIPTION
Misfire: The ECM uses the crankshaft position sensor and camshaft position sensor to monitor changes in
the crankshaft rotation of each cylinder.
The ECM counts the number of times from the engine speed change rate, indicating that misfire has oc-
curred. When the misfire rate equals to or exceeds the count, indicating that the engine condition has deteri-
orated, the CHK ENG is illuminated.
If the misfire rate is high enough and the driving conditions causes the catalyst to overheat, the CHK ENG
blinks when the misfire occurs.
HINT:
For any particular 200 revolutions of engine, misfiring which could result in overheating of catalyst is
detected. This cause CHK ENG to blink (1 trip detection logic).
For any particular 1,000 revolutions of engine, misfiring which could result in a deterioration of emis-
sions is detected. This cause CHK ENG to illuminate (2 trip detection logic).
DTC No.DTC Detecting ConditionTrouble Area
P0300Misfiring of random cylinders is detected
Open or short in engine wire
Connector connection
Vacuum hose connection
PCV hose
Ignition system
P0301
P0302Misfiring of each cylinder is detected
Ignition system
Injector
Fuel pressure
Mass air flow meter
Engine coolant temperature sensor
P0302
P0303
P0304Misfiring of each cylinder is detectedEngine coolant tem erature sensor
Compression pressure
Valve clearance
Valve timing
ECM
HINT:
When 2 or more codes for a misfiring cylinder are recorded repeatedly but no random misfire code is re-
corded, it is indicated that the misfires were detected and recorded at different times.
05C6B±01
±
DIAGNOSTICS SFI SYSTEM(1ZZ±FE/3ZZ±FE)
05±75
AVENSIS REPAIR MANUAL (RM1018E)
CONFIRMATION DRIVING PATTERN
(a)Connect the hand±held tester to the DLC3.
(b)Record the DTC and freeze frame data.
(c)Use the hand±held tester to set to the check mode (See page 05±5).
(d) Read the value on the misfire counter for each cylinder when idling. If \
the value is displayed on the
misfire counter, skip the following procedure of confirmation driving.
(e) Drive the vehicle several times with the engine speed, load and its surr\
ounding range shown with EN- GINE SPD, CALC LOAD in the freeze frame data or MISFIRE RPM, MISFIRE LOAD in\
the data list.
If you do not have the hand±held tester, turn the ignition switch OFF after the symptom is simulated
once. Then repeat the simulation process again.
HINT:
In order to memorize the DTC of the misfire, it is necessary to drive arou\
nd MISFIRE RPM, MISFIRE LOAD
in the following data list. Be sure not to turn the ignition switch OFF, because the diagnosis system is changed
from the check mode to the nomal mode and will result in all of the DTCs and\
the freeze frame data being
erased.
Engine SpeedTime
Idling5 minutes and 45 seconds or more
1,000 rpm4 minutes or more
2,000 rpm2 minutes and 30 seconds or more
3,000 rpm1 minute and 30 seconds or more
(f) Check if there is misfire by monitoring the DTC and the freeze frame data, an\
d then record them.
(g) Turn the ignition switch OFF and wait for at least 5 seconds.
INSPECTION PROCEDURE
HINT:
If the other DTCs besides misfire are memorized simultaneously, perform the troubleshooting for them
first.
Read freeze frame data using \f \b \f\f
Freeze frame data records the engine conditions
when a malfunction is detected. When troubleshooting, it is useful for d\
etermining whether the vehicle
was running or stopped, the engine was warmed up or not, the air±fuel ra\
tio was lean or rich, etc. at
the time of the malfunction.
If the misfire is not occured when the vehicle is brought to the workshop,\
it can be confirmed by repro-
ducing the condition of the freeze frame data. After finishing the repai\
r, confirm that there is no misfire
(See the confirmation driving pattern).
When either of SHORT FT #1 or LONG FT #1 the freeze frame data is over the range of 20%, there
is a possibility that the air±fuel ratio is inclining either to ºR\
ICHº (±20% or less) or ºLEANº (+20% or
more).
When COOLANT TEMP in the freeze frame data is less than 80
C (176
F), there is a possibility of
misfire only during warming up.
In case that the misfire cannot be reproduced, this may be because of th\
e driving with the shortage
of fuel, the use of improper fuel, a stain of ignition plug and etc.
±
DIAGNOSTICS SFI SYSTEM(1ZZ±FE/3ZZ±FE)
05±67
AVENSIS REPAIR MANUAL (RM1018E)
DTCP0171SYSTEM TOO LEAN (FUEL TRIM) (BANK 1)
DTCP0172SYSTEM TOO RICH (FUEL TRIM) (BANK 1)
CIRCUIT DESCRIPTION
Fuel trim refers to the feedback compensation value compared against the basic injection time. Fuel trim
includes short±term fuel trim and long±term fuel trim.
Short±term fuel trim is the short±term fuel compensation used to maintain the a\
ir±fuel ratio at stoichiometric
air±fuel ratio. The signal from the heated oxygen sensor indicates whether the a\
ir±fuel ratio is RICH or LEAN
compared to the stoichiometric air±fuel ratio, This variance triggers a reduc\
tion in fuel volume if the air±fuel
ratio is rich, and an increase in the fuel volume if it is lean.
Long±term fuel trim is overall fuel compensation carried out long±term to comp\
ensate for a continual devi-
ation of the short±term fuel trim from the central value, due to indi\
vidual engine differences, wear over time
and changes in the operating environment.
If both the short±term fuel trim and long±term fuel trim are LEAN or RICH beyond a certain value, it is de\
-
tected as a malfunction and the CHK ENG is illuminated.
DTC No.DTC Detecting ConditionTrouble Area
P0171
When air fuel ratio feedback is stable after warming up engine,
fuel trim is considerably in error on LEAN side
(2 trip detection logic)
Air induction system
Injector blockage
PCV hose
Mass air flow meter
Engine coolant temperature sensor
Fuel pressure
Open or short in heated oxygen sensor circuit
Heated oxygen sensor
ECM
P0172
When air fuel ratio feedback is stable after warming up engine,
fuel trim is considerably in error on RICH side
(2 trip detection logic)
Injector leak, blockage
Mass air flow meter
Engine coolant temperature sensor
Ignition system
Fuel pressure
Open or short in heated oxygen sensor circuit
Gas leakage in exhaust system
Heated oxygen sensor
ECM
HINT:
If the total of the short±term fuel trim value and long±term fuel \
trim value is within 25 %, the system is func-
tioning normally.
WIRING DIAGRAM
Refer to DTC P0125 on page 05±45.
05B3Y±02
05±60
±
DIAGNOSTICS SFI SYSTEM(1ZZ±FE/3ZZ±FE)
AVENSIS REPAIR MANUAL (RM1018E)
DTCP0133OXYGEN SENSOR CIRCUIT SLOW RESPONSE (BANK 1 SENSOR 1)
CIRCUIT DESCRIPTION
Refer to DTC P0125 on page 05±45.
DTC NoDTC Detecting ConditionTrouble Area
P0133
Response time for heated oxygen sensor voltage output to
change from rich to lean, or from lean to rich, is 1.0 sec. or
more during idling after engine is warmed up (2 trip detection
logic)
Open or short in heated oxygen sensor circuit
Heated oxygen sensor
Air induction system
Fuel pressure
Injector
ECM
HINT:
\f
\f
\b
\f
\f
\f
\f
\f
WIRING DIAGRAM
Refer to DTC P0125 on page 05±45.
INSPECTION PROCEDURE
HINT:
Hand±held tester only:
Narrowing down the trouble area is possible by performing ACTIVE TEST of the following \
ºA/F CONTROLº
(heated oxygen sensor or other trouble areas can be distinguished).
(a) Perform ACTIVE TEST using hand±held tester (A/F CONTROL).
HINT:
ºA/F CONTROLº is an ACTIVE TEST which changes the injection volume\
±12.5 % or +25 %.
(1) Connect the hand±held tester to the DLC3 on the vehicle.
(2) Turn the ignition switch ON.
(3) Warm up the engine with the engine speed at 2,500 rpm for approximately. 90 sec.
(4) Select the item ºDIAGNOSIS / OBD/MOBD / ACTIVE TEST / A/F CONTROLº\
.
(5) Perform ºA/F CONTROLº with the engine in an idle condition (press\
the right or left button).
Result:
Heated oxygen sensor reacts in accordance with increase and decrease of injection volume:
+25 % rich output: More than 0.55 V
±12.5 % lean output: Less than 0.4 V
NOTICE:
There is a few second delay in the sensor 1 (front sensor) output, and ther\
e is about 20 seconds delay
in the sensor 2 (rear sensor) output.
05B3W±02
A58686
Vihicle speed40 km/h
(25mph)
IG SW OFF Once
40sec.
or more
60 sec.
or more 10 sec.Twice
40sec.
or more
12 times
40sec.
or more
10 sec.10 sec.
( 1) (
3)
( 4)
Idling( 2) (
3)
( 4) (
3)
( 5)
±
DIAGNOSTICS SFI SYSTEM(1ZZ±FE/3ZZ±FE)
05±55
AVENSIS REPAIR MANUAL (RM1018E)
CONFIRMATION DRIVING PATTERN
1.Connect the hand±held tester to the DLC3. ( 1)
2.Switch the hand±held tester from the normal mode to the check mode (\
See page 05±5). ( 1)
3. Start the engine and let the engine idle for 60 seconds or more. ( 2)
4. Drive the vehicle at 40 km/h (25 mph) or more for 40 seconds or more. \
( 3)
5. Let the engine idle for 10 seconds or more. ( 4)
6. Perform steps 4 to 5 12 times. ( 5)
HINT:
If a malfunction exists, the CHECK ENG will be illuminated on the multi±\
information display during step 6.
NOTICE:
If the conditions in this test are not strictly followed, detection of t\
he malfunction will not be possible.
If you do not have a hand±held tester, turn the ignition switch OFF after performing steps from 3 to
6, then perform steps from 3 to 6 again.
INSPECTION PROCEDURE
HINT:
Hand±held tester only:
Narrowing down the trouble area is possible by performing ACTIVE TEST of the following \
ºA/F CONTROLº
(heated oxygen sensor or other trouble areas can be distinguished).
(a) Perform ACTIVE TEST using hand±held tester (A/F CONTROL).
HINT:
ºA/F CONTROLº is an ACTIVE TEST which changes the injection volume\
±12.5 % or +25 %.
(1) Connect the hand±held tester to the DLC3 on the vehicle.
(2) Turn the ignition switch ON.
(3) Warm up the engine with the engine speed at 2,500 rpm for approximately 9\
0 sec.
(4) Select the item ºDIAGNOSIS / OBD/MOBD / ACTIVE TEST / A/F CONTROLº\
.
(5) Perform ºA/F CONTROLº whith the engine in an idle condition (pres\
s the right or left button).
Result:
Heated oxygen sensor reacts in accordance with increase and decrease of injection volume:
+25 % rich output: More than 0.55 V
±12.5 % lean output: Less than 0.4 V
A66651A±A SectionAir Solid Electrolyte
(Zirconia Element)
Platinum ElectrodeHeater
Exhaust Gas
CoverIdeal Air±Fuel Mixture
Output Voltage
Richer ± Air Fuel Ratio ± Leaner Element
AA
± DIAGNOSTICSSFI SYSTEM (1ZZ±FE/3ZZ±FE)
05±45
AVENSIS REPAIR MANUAL (RM1018E)
DTC P0125 INSUFFICIENT COOLANT TEMP. FOR
CLOSED LOOP FUEL CONTROL
CIRCUIT DESCRIPTION
The heated oxygen sensor is the planar type. Compared to the conventional type, the sensor element and
the heater portions have a narrower overall. The heater can directly conduct its heat to the zirconia element
via the alumina, it helps to accerate the sensor activation.
To obtain a high purification rate for the CO, HC and NOx components of the exhaust gas, a three ± way
catalytic converter is used. For the most efficient use of the three ± way catalytic converter, the air ± fuel ratio
must be precisely controlled so that it is always close to the stoichiometric air ± fuel ratio.
The heated oxygen sensor has the characteristic whereby its output voltage changes suddenly in the vicinity
of the stoichiometric air±fuel ratio. This is used to detect the oxygen concentration in the exhaust gas and
provide the ECM with feedback control the air±fuel ratio.
When the air±fuel ratio becomes LEAN, the oxygen concentration in the exhaust gas increases. And the
heated oxygen sensor informs the ECM of the LEAN condition (low voltage, i. e. less than 0.45 V ).
When the air±fuel ratio is RICHER than the stoichiometric air±fuel ratio, the oxygen concentration in the ex-
haust gas is reduced. And the heated oxygen sensor informs the ECM of the RICH condition (high voltage,
i. e. more than 0.45V). The ECM judges by the voltage output from the heated oxygen sensor whether the
air±fuel ratio is RICH or LEAN and controls the injection time accordingly. If the malfunction of the heated
oxygen sensor causes an output of abnomal voltage, the ECM becomes unable to perform accurate air±fuel
ratio control.
The heated oxygen sensors include a heater which heats the zirconia element. The heater is controlled by
the ECM. When the intake air volume is low (the temperature of the exhaust gas is low), current flows to the
heater in order to heat the sensor for the accurate oxygen concentration detection.
DTC NoDTC Detecting ConditionTrouble Area
P0125
After engine is warmed up, heated oxygen sensor output* does
not change when conditions (a), (b), (c) and (d) continue for at
least 1.5 min:
*: Output value changes at inside of the ECM only
(a) Engine speed: 1,400 rpm or more
(b) Vehicle speed: 40 to 100 km/h (25 to 62 mph)
(c) Throttle valve is not fully closed
(d) 180 sec. or more after starting engineOpen or short in heated oxygen sensor circuit
Heated oxygen sensor
Air induction system
Fuel pressure
Injector
Gas leakage in exhaust system
ECM
05C69±01
A72925
E2
Engine Coolant Temperature Sensor
2
1B±W
BR
E2 THWECM
19
E13
E13 285V
R 05±34
± DIAGNOSTICSSFI SYSTEM (1ZZ±FE/3ZZ±FE)
AVENSIS REPAIR MANUAL (RM1018E)
DTC P0115 ENGINE COOLANT TEMPERATURE CIRCUIT
CIRCUIT DESCRIPTION
A thermistor is built into the engine coolant temperature sensor and changes the resistance value according
to the engine coolant temperature.
The structure of the sensor and connection to the ECM is the same as the ones of the intake air temperature
sensor.
DTC No.DTC Detecting ConditionTrouble Area
P0115Open or short in water temp. sensor circuit
Open or short in Engine coolant temperature sensor circuit
Engine coolant temperature sensor
ECM
If the ECM detects the DTC ºP0115º, it enters the fail±safe mode in which the engine coolant temperature
is assumed to be 80 C (176 F).
HINT:
After confirming DTC P0115, use the hand±held tester to confirm the engine coolant temperature in ºDIAG-
NOSIS / OBD/MOBD / DATA LIST / ALLº.
Temperature DisplayedMalfunction
±40 C (±40 F)Open circuit
140 C (284 F) or moreShort circuit
WIRING DIAGRAM
INSPECTION PROCEDURE
HINT:
Read freeze frame data using
Freeze frame data records the engine conditions
when a malfunction is detected. When troubleshooting, it is useful for determining whether the vehicle
was running or stopped, the engine was warmed up or not, the air±fuel ratio was lean or rich, etc. at
the time of the malfunction.
If different DTCs that are related to a different system are output simultaneously while terminal E2 is
used as a ground terminal, terminal E2 may be open.
05B3Q±02