2005 TOYOTA AVENSIS diagnostic

05–118
– DIAGNOSTICSSFI SYSTEM (1ZZ–FE/3ZZ–FE)(From February, 2004)
AVENSIS REPAIR MANUAL SUPPLEMENT
(RM1098E)
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
When a misfire occurs in the engine, hydrocarbons (HC) enter the exhaust gas in high concentrations. If this
HC concentration is high enough, there could be an increase in exhaust emission levels. High concentra-
tions of HC can also cause temperature of the catalyst to increase, possibly damaging the catalyst. To pre-
vent this increase in emissions and limit the possibility of thermal damage, the ECM monitors the misfire rate.
When the temperature of the catalyst reaches a point of thermal degradation, the ECM will blink the MIL.
For monitoring misfire, the ECM uses both the camshaft position sensor and the crankshaft position sensor.
The camshaft position sensor is used to identify misfiring cylinders and the crankshaft position sensor is used
to measure variations in the crankshaft rotation speed. The misfire counter increments when crankshaft rota-
tion speed variations exceed threshold values.
If the misfiring rate exceeds the threshold and could cause emission deterioration, the ECM illuminates the
MIL.
HINT:
For any particular 200 revolutions of the engine, misfiring which could result in overheating of the cata-
lyst is detected. This will cause the MIL to blink (1 trip detection logic).
For any particular 1,000 revolutions of the engine, misfiring which could result in emission deterioration
is detected. This will cause the MIL to illuminate (2 trip detection logic).
05KOH–02

A78423
20V
/Division Injector Signal Waveform
20V
/Division
GND
100 msec./Division (Idling)(Magnification)
GND
1 msec./Division (Idling)
Injection Duration
– DIAGNOSTICSSFI SYSTEM (1ZZ–FE/3ZZ–FE)(From February, 2004)
05–119
AVENSIS REPAIR MANUAL SUPPLEMENT
(RM1098E)DTC No.
DTC Detection ConditionTrouble Area
P0300Misfiring of random cylinders is detected
Open or short in engine wire harness
Connector connection
Vacuum hose connection
Ignition system
Injector
Fuel pressure
Mass air flow meter
Engine coolant temperature sensor
Compression pressure
Valve clearance
Valve timing
PCV hose connection
PCV hose
ECM
P0301
P0302
Misfiring of each cylinder is detected
Open or short in engine wire harness
Connector connection
Vacuum hose connection
Ignition system
Injector
Fuel pressure
Mass air flow meter
P0303
P0304Misfiring of each cylinder is detectedEngine coolant temperature sensor
Compression pressure
Valve clearance
Valve timing
PCV hose connection
PCV hose
ECM
HINT:
When the DTCs for misfiring cylinders are recorded repeatedly but no random misfire DTC is recorded, it
indicates that the misfires have been set and recorded at different times.
Reference: Inspection using the oscilloscope
With the engine idling, check the waveform between terminals #10 to #40 and E01 of the ECM connectors.
ItemContents
Terminal#10 to #40 – E01
Equipment Setting20V/Division, 100 or 1 ms/Division
ConditionIdling
HINT:
The correct waveform is as shown.

A76891
I13
Ignition Switch
4 6
B–R B–R
IE4 (LHD)
1
1 IP1
(RHD) DH
2
DL 16
Driver
Side J/B
IGN
B–R
1 AM2 IG2
1
2
2
1
1A1 1Engine
Room
R/B No.1
Engine
Room
J/B No.1
B–G
4A
1
4B1 Engine
Room
J/B No.4 B–R 2R–B 1
I5
Injector No.1
B–R
Y
W
B 1
#10
E13
2 #20
E13
#30
3
E13
4 #40
E13
7 E01
E13
E02
6
E13
W–B
W–B ECM
R–B R–B
R–B
R–B
R–B 21
I6
Injector No.2
21
I7
Injector No.3
21
I8
Injector No.4
EA18
4
13
25 IG2
Relay
B
W–B
B
EC EG
4
44 Engine
Room
R/B No.4
B–G
FL MAIN
Battery R–B
05–120
–
DIAGNOSTICS SFI SYSTEM (1ZZ–FE/3ZZ–FE)(From February, 2004)
AVENSIS REPAIR MANUAL SUPPLEMENT
(RM1098E)
WIRING DIAGRAM
Refer to DTC P0351 on page 05–143 for the wiring diagram of the ignition system.

–
DIAGNOSTICS SFI SYSTEM (1ZZ–FE/3ZZ–FE)(From February, 2004)
05–121
AVENSIS REPAIR MANUAL SUPPLEMENT
(RM1098E)
CONFIRMATION DRIVING PATTERN
(a) Connect the intelligent tester II to the DLC3.
(b) Turn the ignition switch to ON and turn the intelligent tester II ON.
(c) Note down the DTC(s) and freeze frame data.
(d) Switch the ECM from normal mode to check mode using the intelligent test\
er II ( see page 05–20).
(e) Check the misfire counter values for each cylinder when idling. If the misfire counter value indicates 0, perform the following procedure of the confirmation driving pattern.
(f) Drive the vehicle several times using an engine speed (Engine Speed), \
engine load (Calculate Load) and other data stored in the freeze frame data.
If you have no intelligent tester II, turn the ignition switch to OFF afte\
r the symptom is simulated once. Then
repeat the simulation process again.
HINT:
In order to record the misfire DTCs, it is necessary to drive around Misfir\
e RPM and Misfire Load in Data List
for the following period of time. Do not turn the ignition switch to OFF. Turning the ignition switch to OFF
switches the diagnosis system from check mode to normal mode. So all DTCs and ot\
her data will be erased.
Engine SpeedTime
Idling3 minutes 30 seconds or more
1,000 rpm3 minutes or more
2,000 rpm1 minute 30 seconds or more
3,000 rpm1 minute or more
(g) Check if there is the DTC(s) to verify whether misfires have occurred. If t\
he DTC(s) is present, record
the DTC and freeze frame data.
(h) Turn the ignition switch to OFF and wait for at least 5 seconds.

05–122
–
DIAGNOSTICS SFI SYSTEM (1ZZ–FE/3ZZ–FE)(From February, 2004)
AVENSIS REPAIR MANUAL SUPPLEMENT
(RM1098E)
INSPECTION PROCEDURE
HINT:
If any DTCs other than the misfire DTCs are set simultaneously, first troubleshoot them.
If a misfire does not occur when the vehicle is brought to the workshop, a mi\
sfire can be confirmed by
reproducing the condition of the freeze frame data. Also, after finishing repairs, \
confirm that misfires
do not recur (see the confirmation driving pattern).
Read freeze frame data using the intelligent tester II. Freeze frame dat\
a record the engine condition
when malfunctions are detected. When troubleshooting, freeze frame data \
can help determine if the
vehicle was moving or stationary, if the engine was warmed up or not, if the air–fuel ratio was lean \
or
rich, and other data from the time the malfunction occurred.
On 6 and 8 cylinder engines, misfiring cylinders cannot be identified at\
high engine speed and only
a general misfire DTC P0300 is stored instead of the individual misfiring\
cylinder DTCs (P0301 to
P0308).
If a misfire starts in a high engine speed area or a misfire occurs only i\
n a high engine speed area, only
DTC P0300 may be stored.
When only a general misfire DTC P0300 is stored:
Erase the general misfire DTC from the ECM using the intelligent tester \
II.
Start the engine and perform the confirmation driving pattern.
Check the value of the misfire ratio for each cylinder. Or check the DTC(s).
Perform repairs on the cylinder that has a high misfire ratio. Or repair the cy\
linder indicated by the DTC.
After finishing repairs, perform the confirmation driving pattern again and c\
onfirm that no misfire oc-
curs.
When either of Short FT #1 and Long FT #1 in the freeze frame data is over the range of 20 %, there
is a possibility that the air–fuel ratio is becoming rich (–20 % \
or less) or lean (+20 % or more).
When Coolant Temp in the freeze frame data is less than 80
C (176
F), there is a possibility that mis-
fires occur only during engine warm–up.
If a misfire cannot be reproduced, the following reasons may apply: 1) th\
e vehicle has low fuel, 2) im-
proper fuel is being used, and 3) the ignition plug has been contaminated.
Be sure to check the misfire counter value after repairs.
1 CHECK OTHER DTC OUTPUT(IN ADDITION TO MISFIRE DTCS)
(a) Connect the intelligent tester II to the DLC3.
(b) Turn the ignition switch to ON and turn the intelligent tester ll ON.
(c) Select the following menu items: Powertrain / Engine and ECT / DTC.
(d) Read DTCs. Result:
Display (DTC Output)Proceed To
P0300, P0301, P0302, P0303 and/or P0304A
P0300, P0301, P0302, P0303 or P0304 and other DTCsB
HINT:
If any DTCs other than P0300, P0301, P0302, P0303
or P0304 are output, troubleshoot those DTCs.
B GO TO RELEVANT DTC CHART (See page 05–27 )
A

– DIAGNOSTICSSFI SYSTEM (1ZZ–FE/3ZZ–FE)(From February, 2004)
05–123
AVENSIS REPAIR MANUAL SUPPLEMENT
(RM1098E)
2 CHECK WIRE HARNESS, CONNECTOR AND VACUUM HOSE IN ENGINE ROOM
(a) Check the connection condition of the wire harnesses and connector.
(b) Check the piping of the vacuum hose.
(c) Check the vacuum hose for disconnection or breakage.
OK: Connected correctly and no damage on the wire harnesses.
NG REPAIR OR REPLACE, THEN CONFIRM THAT
THERE IS NO MISFIRE
OK
3 CHECK CONNECTION OF PCV HOSE
OK: The PCV hose is connected correctly and not damaged.
NG REPAIR OR REPLACE PCV HOSE
OK
4 READ VALUE OF INTELLIGENT TESTER II(NUMBER OF MISFIRING CYLINDERS)
(a) Connect the intelligent tester II to the DLC3.
(b) Turn the ignition switch to ON and turn the intelligent tester ll ON.
(c) Start the engine.
(d) On the intelligent tester II, select the following menu items: Powertrain / Engine and ECT / Data List
/ Cylinder #1 Misfire Rate – Cylinder #4 Misfire Rate.
(e) Check the number of misfiring cylinders on the intelligent tester II.
HINT:
When a misfire is not reproduced, be sure to proceed according to the table below based on the stored DTC.
Result:
High Misfire Rate CylinderProceed To
1 or 2 cylindersA
3 cylinders or moreB
B Go to step 15
A

A81912
1.0 to 1.1 mm
(0.039 to 0.043 in.)
05–124
– DIAGNOSTICSSFI SYSTEM (1ZZ–FE/3ZZ–FE)(From February, 2004)
AVENSIS REPAIR MANUAL SUPPLEMENT
(RM1098E)
5 CHECK SPARK PLUG AND SPARK OF MISFIRING CYLINDER
(a) Remove the ignition coil assembly.
(b) Remove the spark plug.
(c) Check the spark plug type.
Recommended spark plug:
SupplierType
DENSOK16R–U11
(d) Check the spark plug electrode gap.
Standard: 1.0 to 1.1 mm (0.039 to 0.043 in.)
Maximum: 1.3 mm (0.047 in.)
NOTICE:
If adjusting the gap of a new spark plug, bend only the
ground electrode. Do not touch the tip. Never attempt to ad-
just the gap of a used plug.
(e) Check the electrode for carbon deposits.
(f) Perform a spark test.
CAUTION:
Completely disconnect each injector connector.
NOTICE:
Do not crank the engine for more than 5 to 10 seconds.
(1) Install the spark plug to the ignition coil, and connect
the ignition coil connector.
(2) Disconnect the injector connector.
(3) Ground the spark plug.
(4) Check if a spark occurs while the engine is being
cranked.
OK: A spark jumps across electrode gap.
(g) Reinstall the spark plug.
(h) Reinstall the ignition coil assembly.
OK Go to step 8
NG

– DIAGNOSTICSSFI SYSTEM (1ZZ–FE/3ZZ–FE)(From February, 2004)
05–125
AVENSIS REPAIR MANUAL SUPPLEMENT
(RM1098E)
6 CHANGE NORMAL SPARK PLUG AND CHECK SPARK OF MISFIRING CYLINDER
(a) Change the spark plug with the normal spark plug.
(b) Perform a spark test.
CAUTION:
Completely disconnect each injector connector.
NOTICE:
Do not crank the engine for more than 5 to 10 seconds.
(1) Install the spark plug to the ignition coil, and connect the ignition coil connector.
(2) Disconnect the injector connector.
(3) Ground the spark plug.
(4) Check if a spark occurs while the engine is being cranked.
OK: A spark jumps across electrode gap.
OK REPLACE IGNITION COIL ASSY
NG