TOYOTA AVALON 2001 Service Repair Manual
Manufacturer: TOYOTA, Model Year: 2001, Model line: AVALON, Model: TOYOTA AVALON 2001Pages: 1897, PDF Size: 26.61 MB
Page 941 of 1897
FI6588
FI6538
A00064
10 V
/Division10 V
/Division
GND GND
100 msec./Division (Idling)1 msec./Division (Idling)
Injection duration
(Magnification) Injector Signal Waveform
DI-62
- DIAGNOSTICSENGINE
218 Author: Date:
2001 AVALON (RM808U)
Reference: INSPECTION USING OSCILLOSCOPE
With the engine idling, check the waveform between terminals #10 - #60 and E01 of the ECM connector.
HINT:
The correct waveform is as shown.
OK Go to step 5.
NG
4 Check resistance of injector of misfiring cylinder (See page SF-19).
NG Replace injector.
OK
Check for open and short in harness and con-
nector between injector and ECM (See page
IN-30).
5 Check fuel pressure (See page SF-6).
NG Check and repair fuel pump, fuel pipe line and
filter (See page SF-1).
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.
Page 945 of 1897
DI-66
- DIAGNOSTICSENGINE
222 Author: Date:
2001 AVALON (RM808U)
Type I
2 Check for open and short in harness and connector between EB1 connector and
ECM (See page IN-30).
NG Repair or replace harness or connector.
OK
Check and replace ECM (See page IN-30).
3 Check for open and short in harness and connector between EB1 connector and
knock sensor (See page IN-30).
HINT:
If DTC P0325 has changed to P0330, check the knock sensor circuit on the right bank side.
If DTC P0330 has changed to P0325, check the knock sensor circuit on the left bank side.
NG Repair or replace harness or connector.
OK
Replace knock sensor.
Page 946 of 1897
A11084
Right Bank VVT Sensor (Camshaft Position Sensor)
Crankshaft Position Sensor1
2
1
2
B-W B-W
L
L16
2410ECM
VV1+
NE+
NE-
E2
21LB-W
LE4
E5
VV2+ 22 Left Bank VVT Sensor (Camshaft Position Sensor)E5
E4 CC
C
CJ8 J/C
- DIAGNOSTICSENGINE
DI-67
223 Author: Date:
2001 AVALON (RM808U)
DTC P0335 Crankshaft Position Sensor ºAº Circuit Mal-
function
CIRCUIT DESCRIPTION
Crankshaft position sensor (NE signal) consists of a magnet, iron core and pickup coil.
The NE signal plate has 34 teeth and is installed the crankshaft timing pulley. The NE signal sensor gener-
ates 34 signals at every engine revolution. The ECM detects the standard crankshaft angle based on the
G (VV) signal, and the actual crankshaft angle and the engine speed by the NE signal.
DTC No.DTC Detecting ConditionTrouble Area
P0335
No crankshaft position sensor signal to ECM during cranking
(2 trip detection logic)Open or short in crankshaft position sensor circuit
Crankshaft position sensor
P0335No crankshaft position sensor signal to ECM with engine
speed 600 rpm or more (2 trip detection logic)
Crankshaft osition sensor
Crankshaft timing pulley
ECM
WIRING DIAGRAM
INSPECTION PROCEDURE
HINT:
Perform troubleshooting of DTC P0335 first. If no trouble is found, troubleshoot the following mechani-
cal systems.
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.
DI07U-09
Page 947 of 1897
A11663
VV1, VV2 and NE Signal Waveforms2 V
/Division
20 msec./Division (Idling)
VV1
NE VV2GND
GND
GND
DI-68
- DIAGNOSTICSENGINE
224 Author: Date:
2001 AVALON (RM808U)
1 Check resistance of crankshaft position sensor (See page IG-9).
Reference: INSPECTION USING OSCILLOSCOPE
During cranking or idling, check the waveforms between termi-
nals VV1 and NE-, VV2 and NE-, and NE and NE- of the ECM
connectors.
HINT:
The correct waveforms are as shown.
NG Replace crankshaft position sensor.
OK
2 Check for open and short in harness and connector between ECM and crank-
shaft position sensor (See page IN-30).
NG Repair or replace harness or connector.
OK
3 Inspect sensor installation and signal plate teeth of crankshaft timing pulley.
NG Tighten sensor. Replace crankshaft timing
pulley.
OK
Check and replace ECM (See page IN-30).
Page 948 of 1897
- DIAGNOSTICSENGINE
DI-69
225 Author: Date:
2001 AVALON (RM808U)
DTC P0340 Camshaft Position Sensor Circuit Malfunc-
tion
CIRCUIT DESCRIPTION
Camshaft position sensor (G (VV) signal) consists of a magnet, iron core and pickup coil.
The G (VV) signal plate has 3 teeth, on its outer circumference and is installed the camshaft timing gear.
When the camshafts rotate, the protrusion on the signal plate and the air gap on the pickup coil change,
causing fluctuations in the magnetic field and generating an electromotive force in the pickup coil.
The NE signal plate has 34 teeth and is installed the crankshaft timing pulley. The NE signal sensor gener-
ates 34 signals at every engine revolution. The ECM detects the standard crankshaft angle based on the
G (VV) signal and the actual crankshaft angle and the engine speed by the NE signal.
DTC No.DTC Detecting ConditionTrouble Area
P0340
No camshaft position sensor signal to ECM during cranking (2
trip detection logic)Open or short in camshaft position sensor circuit
Camshaft position sensor
P0340No camshaft position sensor signal to ECM with engine speed
600 rpm or more
Camshaft osition sensor
Camshaft timing gear
ECM
WIRING DIAGRAM
Refer to DTC P0335 on page DI-67.
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 resistance of camshaft position sensor (See page IG-1).
Reference: INSPECTION USING OSCILLOSCOPE
Refer to DTC P0335 on page DI-67.
NG Replace camshaft position sensor.
OK
2 Check for open and short in harness and connector between ECM and camshaft
position sensor (See page IN-30).
NG Repair or replace harness or connector.
DI07V-09
Page 949 of 1897
DI-70
- DIAGNOSTICSENGINE
226 Author: Date:
2001 AVALON (RM808U)
OK
3 Inspect sensor installation and signal plate teeth of camshaft timing gear.
NG Tighten sensor. Replace camshaft timing gear.
OK
Check and replace ECM (See page IN-30).
Page 950 of 1897
A01674
Waveform of
A/F Sensor
Normal CatalystWaveform of Heated Oxygen
Sensor behind Catalyst
Abnormal Catalyst
- DIAGNOSTICSENGINE
DI-71
227 Author: Date:
2001 AVALON (RM808U)
DTC P0420 Catalyst System Efficiency Below Threshold
(Bank 1)
CIRCUIT DESCRIPTION
The ECM observes the waveform of the heated oxygen sensor located behind the catalyst to determine
whether the catalyst performance has deteriorated.
If the catalyst is functioning normally, the waveform of the heated oxygen sensor located behind the catalyst
switches back and forth between rich and lean much more slowly.
When the waveform of the heated oxygen sensor located behind the catalyst alternates flutteringly between
rich and lean, it indicates that catalyst performance has deteriorated.
DTC No.DTC Detecting ConditionTrouble Area
P0420
After engine and catalyst are warmed up, and while vehicle is
driven within set vehicle and engine speed range, waveform of
heated oxygen sensor (bank 1 sensor 2) alternates flutteringly
between rich and lean (2 trip detection logic)Gas leakage on exhaust system
A/F sensor (bank 1, 2 sensor 1)
Heated oxygen sensor (bank 1 sensor 2)
Three-way catalytic converter
DI6T5-01