Page 2505 of 4770
± DIAGNOSTICSENGINE (5S±FE)
DI±85
320 Author: Date:
INSPECTION PROCEDURE
HINT:
Read freeze frame data using TOYOTA hand±held tester or OBD II scan tool. Because freeze frame records
the engine conditions when the malfunction is detected, when troubleshooting it is useful for determining
whether the vehicle was running or stopped, the engine warmed up or not, the air±fuel ratio lean or rich, etc.
at the time of the malfunction.
1 Check air induction system (See page SF±1).
NG Repair or replace.
OK
2 Check injector injection (See page SF±23).
NG Replace injector.
OK
3 Check manifold absolute pressure sensor and engine coolant temp. sensor
(See pages SF±53 and SF±49).
NG Repair or replace.
OK
4 Check for spark and ignition (See page IG±1).
NG Repair or replace.
OK
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± DIAGNOSTICSENGINE (5S±FE)
321 Author: Date:
5 Check fuel pressure (See page SF±6).
NG Check and repair fuel pump, pressure regulator,
fuel pipe line and filter.
OK
6 Check gas leakage on exhaust system.
NG Repair or replace.
OK
Check and replace ECM (See page IN±31).
Page 2507 of 4770
P18349
± DIAGNOSTICSENGINE (5S±FE)
DI±87
322 Author: Date:
7 Check the output voltage of heated oxygen sensor during idling.
PREPARATION:
Warm up the heated oxygen sensor the engine at 2,500 rpm for approx. 90 sec.
CHECK:
Use the OBD II scan tool or TOYOTA hand±held tester to read the output voltage of the heated oxygen sen-
sor during idling.
OK:
Heated oxygen sensor output voltage:
Alternates repeatedly between less than 0.4 V and more than 0.55 V (See the following table).
OK Go to step 9.
NG
8 Check for open and short in harness and connector between ECM and oxygen
sensor (See page IN±31).
NG Repair or replace harness or connector.
OK
Replace oxygen sensor.
Page 2508 of 4770
DI±88
± DIAGNOSTICSENGINE (5S±FE)
323 Author: Date:
9 Perform confirmation driving pattern (See page DI±66).
Go
10 Is there DTC P0171 or P0172 being output again?
YES Check and replace ECM.
NO
11 Did vehicle runs out of fuel in the past?
NO Check for intermittent problems.
YES
DTC P0171 or P0172 is caused by running out of fuel.
Page 2509 of 4770

± DIAGNOSTICSENGINE (5S±FE)
DI±89
324 Author: Date:
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 for each cylinder.
The ECM counts the number of times the engine speed change rate indicates that misfire has occurred. And
when the misfire rate equals or exceeds the count indicating that the engine condition has deteriorated, the
MIL lights up.
If the misfire rate is high enough and the driving conditions will cause catalyst overheating, the MIL blinks
when misfiring occurs.
DTC No.DTC Detecting ConditionTrouble Area
P0300Mi fi i f d li d i d t t d d i ti l
Ignition system
Injector
Fuel line pressure
EGR
P0300
P0301
P0302
P0303
P0304
Misfiring of random cylinders is detected during any particular
200 or 1,000 revolutions
For any particular 200 revolutions for engine, misfiring is de-
tected which can cause catalyst overheating
(This causes MIL to blink)
EGR
Compression pressure
Valve clearance not to specification
Valve timing
Manifold absolute pressure sensor
P0304(This causes MIL to blink)Manifold absolute ressure sensor
Engine coolant temp. sensor
Open or short in engine wire
Connector connection
ECM
HINT:
When the 2 or more codes for a misfiring cylinder are recorded repeatedly but no random misfire code is
recorded, it indicates that the misfires were detected and recorded at different times.
DI011±07
Page 2510 of 4770
A03626
ECM
#10
#20
#30
#40
E01
E02 Injector
No. 1
No. 2
No. 3
No. 4E9
E9
E9
E9
E9
E912
11
25
24
13
26 1
1
1
1 2
2
2
2L
R
Y
W
BR
BR B±R
B±R
B±R
B±R B
B
BB J21
J/CB B±R B±R
W±R
B±G
B
B±RIG Switch Battery
Instrument
Panel J/B
Engine Room
J/B No. 2 FL
Block 1
1
AM2
2L 4
2A 11C8
1K3
1K5
1B 5
MAIN
FL
EC II3 12
W±R
F4
F6 6
7
*1: w/o Immobiliser
*2: w/ Immobiliser(*1) (*2)
E910
E99
(*1) (*2)
DI±90
± DIAGNOSTICSENGINE (5S±FE)
325 Author: Date:
WIRING DIAGRAM
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± DIAGNOSTICSENGINE (5S±FE)
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326 Author: Date:
CONFIRMATION DRIVING PATTERN
(1) Connect the TOYOTA hand±held tester or OBD II scan tool.
(2) Record DTC and the freeze frame data.
(3) Use the TOYOTA hand±held tester to set to Check Mode. (See page DI±3)
(4) Drive the vehicle several times with the engine speed, load and its surrounding range shown with
ENGINE SPD, CALC LOAD in the freeze frame data or MISFIRE RPM, MISFIRE LOAD in the data list.
If you have no TOYOTA hand±held tester, turn the ignition switch OFF after the symptom is simulated
the first time. Then repeat the simulation process again.
HINT:
In order to memorize DTC of misfire, it is necessary to drive around MISFIRE RPM, MISFIRE LOAD in the
data list for the following period of time.
Engine SpeedTime
Idling3 minutes 30 seconds or more
1000 rpm3 minutes or more
2000 rpm1 minutes 30 seconds or more
3000 rpm1 minutes or more
(5) Check whether there is misfire or not by monitoring DTC and the freeze frame data. After that, record
them.
(6) Turn the ignition switch OFF and wait at least 5 seconds.
Page 2512 of 4770

DI±92
± DIAGNOSTICSENGINE (5S±FE)
327 Author: Date:
INSPECTION PROCEDURE
HINT:
If is the case that DTC besides misfire is memorized simultaneously, first perform the troubleshooting
for them.
Read freeze frame data using TOYOTA hand±held tester or OBD II scan tool. Because freeze frame
data records the engine conditions when the malfunction is detected, when troubleshooting it is useful
for determining whether the vehicle was running or stopped, the engine warmed up or not, the air±fuel
ratio lean or rich, etc. at the time of the malfunction.
When the vehicle is brought to the workshop and the misfire is not occurred, misfire can be confirmed
by reproducing the condition or freeze frame data. Also, after finishing the repair, confirm that there
is no misfire. (See the confirmation driving pattern)
When either of SHORT FT #1, LONG FT #1, SHORT FT #2 or LONG FT #2 in the freeze frame data
is besides the range of ±20%, there is a possibility that the air±fuel ratio is inclining either to ºrichº
(±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 or
misfire only during warming up.
In the case that misfire cannot be reproduced, the reason may be because of the driving with lack or
fuel, the use of improper fuel, a stain of ignition plug, and etc.
1 Check wire harness, connector and vacuum hose in engine room.
CHECK:
(a) Check the connection conditions of the wire harness and connector.
(b) Check the disconnection, piping and break of the vacuum hose.
NG Repair or replace, then confirm that there is no
misfire (See the confirmation driving pattern).
OK