sensor TOYOTA AVALON 2001 Service Repair Manual
[x] Cancel search | Manufacturer: TOYOTA, Model Year: 2001, Model line: AVALON, Model: TOYOTA AVALON 2001Pages: 1897, PDF Size: 26.61 MB
Page 931 of 1897
- DIAGNOSTICSENGINE
DI-47
203 Author: Date:
2001 AVALON (RM808U)
8 Check gas leakage on exhaust system.
NG Repair or replace
OK
Replace A/F sensor (bank 1, 2 sensor 1).
9 Perform confirmation driving pattern (See page DI-106).
Go
10 Is there DTC P0125 being output again?
YES Check and replace ECM (See page IN-30).
NO
11 Did vehicle runs out of fuel in past?
NO Check for intermittent problems
(See page DI-3).
YES
DTC P0125 is caused by running out of fuel.
Page 932 of 1897
DI-48
- DIAGNOSTICSENGINE
204 Author: Date:
2001 AVALON (RM808U)
DTC P0128 Thermostat Malfunction
CIRCUIT DESCRIPTION
If the water temperature becomes 75°C (167°F) or more, it is abnormal.
If not due to the thermostat malfunction, it is abnormal.
DTC No.DTC Detecting ConditionTrouble Area
P0128
Condition (a), (b) or (c):
(a) After starting engine at 20°C (68°F)
(b) After engine is warmed up
(c) THW < 75°C (167°F)Thermostat
Cooling system
Engine coolant temp. sensor
ECM
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 was warmed up or not, the air-fuel ratio was lean
or rich, etc. at the time of the malfunction.
1 Check thermostat (See page CO-1 1).
NG Replace thermostat.
YES
2 Are there any other codes (besides DTC P0128) being output?
YES Go to relevant DTC chart (See page DI-14).
NG
Check and replace ECM (See page IN-30).
DI6T2-01
Page 933 of 1897
- DIAGNOSTICSENGINE
DI-49
205 Author: Date:
2001 AVALON (RM808U)
DTC P0136 Oxygen Sensor Circuit Malfunction (Bank 1
Sensor 2)
CIRCUIT DESCRIPTION
Refer to DTC P0125 on page DI-43.
DTC No.DTC Detecting ConditionTrouble Area
P0136
Voltage output of heated oxygen sensor remains at 0.4 V or
more or 0.55 V or less when vehicle is driven at 50 km/h (31
mph) or more after engine is warmed up (2 trip detection logic)Open or short in heated oxygen sensor circuit
Heated oxygen sensor
HINT:
Bank 1 refers to the bank that includes cylinder No.1.
Sensor 2 refers to the sensor farther away from the engine body.
WIRING DIAGRAM
Refer to DTC P0125 on page DI-43.
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 was warmed up or not, the air-fuel ratio was lean
or rich, etc. at the time of the malfunction.
1 Are there any other codes (besides DTC P0136) being output?
YES Go to relevant DTC chart (See page DI-14).
NO
2 Check for open and short in harness and connector between ECM and heated
oxygen sensor (See page IN-30).
NG Repair or replace harness or connector.
OK
DI07Q-09
Page 934 of 1897
DI-50
- DIAGNOSTICSENGINE
206 Author: Date:
2001 AVALON (RM808U)
3 Check output voltage of heated oxygen sensor.
PREPARATION:
(a) Connect the OBD II scan tool or TOYOTA hand-held tester to the DLC3.
(b) Warm up the engine to normal operating temperature.
CHECK:
Read the voltage output of the heated oxygen sensor when the engine is suddenly raced.
HINT:
Perform quick racing to 4,000 rpm 3 min. using the accelerator pedal.
OK:
Heated oxygen sensor output voltage: Alternates from 0.4 V or less to 0.6 V or more.
OK Check that each connector is properly con-
nected.
NG
Replace heated oxygen sensor.
Page 935 of 1897
A06104
ON
HTS
(+)
(-)
- DIAGNOSTICSENGINE
DI-51
207 Author: Date:
2001 AVALON (RM808U)
DTC P0141 Oxygen Sensor Heater Circuit Malfunction
(Bank 1 Sensor 2)
CIRCUIT DESCRIPTION
Refer to DTC P0125 on page DI-43.
DTC No.DTC Detecting ConditionTrouble Area
P0141
When heater operates, heater current exceeds 2.35 A (2 trip
detection logic)Open or short in heater circuit of heated oxygen sensor
Htd htP0141Heater current of 0.2 A or less when heater operates (2 trip
detection logic)Heated oxygen sensor heater
ECM
HINT:
Bank 1 refers to the bank that includes cylinder No.1.
Sensor 2 refers to the sensor farther away from the engine body.
WIRING DIAGRAM
Refer to DTC P0125 on page DI-43.
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 was warmed up or not, the air-fuel ratio was lean
or rich, etc. at the time of the malfunction.
1 Check voltage between terminal HTS of ECM connector and body ground.
PREPARATION:
(a) Remove the glove compartment (See page SF-82).
(b) Turn the ignition switch ON.
CHECK:
Measure the voltage between terminal HTS of the ECM con-
nector and body ground.
OK:
Voltage: 9 - 14 V
OK Check and replace ECM (See page IN-30).
NG
2 Check resistance of heated oxygen sensor heater (See page SF-81).
NG Replace heated oxygen sensor.
DI6T3-01
Page 936 of 1897
DI-52
- DIAGNOSTICSENGINE
208 Author: Date:
2001 AVALON (RM808U)
OK
Check and repair harness or connector between EFI main relay (Marking: EFI) and heated oxygen
sensor, and heated oxygen sensor and ECM (See page IN-30).
Page 937 of 1897
DI-58
- DIAGNOSTICSENGINE
214 Author: Date:
2001 AVALON (RM808U)
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
DTC P0305 Cylinder 5 Misfire Detected
DTC P0306 Cylinder 6 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.
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
P0300Misfiring of random cylinders is detected during any particular
200 or 1,000 revolutionsOpen or short in engine wire
Connector connection
Vacuum hose connection
P0301
P0302
P0303For any particular 200 revolutions for engine, misfiring is de-
tected which can cause catalyst overheating (This causes MIL
to blink)
Ignition system
Injector
Fuel pressure
Mass air flow meter
Engine coolant tempsensorP0303
P0304
P0305
P0306For any particular 1,000 revolutions of engine, misfiring is de-
tected which causes a deterioration in emission (2 trip detec-
tion logic)
Engine coolant temp. sensor
Compression pressure
Valve clearance
Valve timing
ECM
DI07S-10
Page 942 of 1897
- DIAGNOSTICSENGINE
DI-63
219 Author: Date:
2001 AVALON (RM808U)
OK
6 Check injector injection (See page SF-23).
NG Replace injector.
OK
7 Check mass air flow meter (See page SF-31) and engine coolant temperature
sensor (See page SF-73).
NG Repair or replace.
OK
Check compression pressure (See page
EM-3), valve clearance (See page EM-4) and
valve timing (See page EM-21).
Page 943 of 1897
A03315
Knock Sensor 1
(on Right Bank)
Knock Sensor 2
(on Left Bank)EB1 1
1W
W1
2W
WE4ECM
27
28KNKR
KNKLE1
E1 E4 EB1 DI-64
- DIAGNOSTICSENGINE
220 Author: Date:
2001 AVALON (RM808U)
DTC P0325 Knock Sensor 1 Circuit Malfunction (Bank 1)
DTC P0330 Knock Sensor 2 Circuit Malfunction (Bank 2)
CIRCUIT DESCRIPTION
Each of knock sensor is fitted to the right bank and left bank of the cylinder block to detect engine knocking.
This sensor contains a piezoelectric element which generates a voltage when it becomes deformed, which
occurs when the cylinder block vibrates due to knocking. If engine knocking occurs, ignition timing is retarded
to suppress it.
DTC No.DTC Detecting ConditionTrouble Area
P0325No knock sensor 1 signal to ECM with engine speed between
2,000 rpm and 5,600 rpmOpen or short in knock sensor 1 circuit
Knock sensor 1 (looseness)
ECM
P0330No knock sensor 1 signal to ECM with engine speed between
2,000 rpm and 5,600 rpmOpen or short in knock sensor 2 circuit
Knock sensor 2 (looseness)
ECM
If the ECM detects the above diagnosis conditions, it operates the fail-safe function in which the corrective
retard angle value is set to the maximum value.
WIRING DIAGRAM
INSPECTION PROCEDURE
HINT:
DTC P0325 is for the right bank knock sensor circuit.
DTC P0330 is for the left bank knock sensor circuit.
DI07T-09
Page 944 of 1897
A00304
Knock SensorECM
EB1
Male
ConnectorFemale
Connector 1
111
22KNKR
KNKL
EB1
E4
E427
28
FI7050
S06024
S06025
FI6510FI6607A00113
KNK Signal Waveform
0.5 V
/Division
5 msec./Division
100 msec./Division 0V
200 mV
/Division
0V
- DIAGNOSTICSENGINE
DI-65
221 Author: Date:
2001 AVALON (RM808U)
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 was warmed up or not, the air-fuel
ratio was lean or rich, etc. at the time of the malfunction.
1 Connect OBD II scan tool or TOYOTA hand-held tester, and check knock sensor
circuit.
PREPARATION:
(a) Connect the OBD II scan tool or TOYOTA hand-held tes-
ter to the DLC3.
(b) Disconnect the wire from wire connector EB1.
(c) Connect the terminals of the disconnected EB1 male con-
nector and EB1 female as follows.
Male connector eFemale connector
Terminal 1 e Terminal 2
Terminal 2 e Terminal 1
(d) Turn the ignition switch ON and push the OBD II scan tool
or TOYOTA hand-held tester main switch ON.
(e) After the engine is warmed up, perform quick racing to
4,000 rpm 3 times.
CHECK:
Check the DTC.
RESULT:
Type IDTC same as when vehicle brought in
P0325 " P0325 or P0330 " P0330
Type IIDTC different to when vehicle brought in
P0325 " P0330 or P0330 " P0325
Reference: INSPECTION USING OSCILLOSCOPE
With the engine racing (4,000 rpm), check the waveform
between terminals KNKR, KNKL of the ECM connector
and body ground.
HINT:
The correct waveform is as shown.
Spread the time on the horizontal axis, and confirm that
period of the wave is 141 msec. (Normal mode vibration
frequency of knock sensor: 7.1 kHz)
HINT:
If normal mode vibration frequency is not 7.1 kHz, the sensor
is malfunctioning.
Type II Go to step 3.