TOYOTA AVALON 2001 Service Repair Manual
Page 981 of 1897
P01559
Throttle Valve
From
Air
Cleaner
Signal
ECM
ValveIAC Valve
To Cylinders Intake Air Chamber
A11664
From Battery2G1 2
4 EFI
No.1EFI Relay
1 23
52A
2B 2F
J7
J/C IAC Valve
G-B
BR
21
3E4ECM
RSO
E01
EC26
A B-W
L-O
BRA
4EFI
No.2
B
W-B
EDEngine Room J/B
EBA
From
Terminal
MREL of
ECM
DI-102
- DIAGNOSTICSENGINE
258 Author: Date:
2001 AVALON (RM808U)
DTC P0505 Idle Control System Malfunction
CIRCUIT DESCRIPTION
The rotary solenoid type IAC valve is located in front of the in-
take air chamber and intake air bypassing the throttle valve is
directed to the IAC valve through a passage.
In this way the intake air volume bypassing the throttle valve is
regulated, controlling the engine speed.
The ECM operates only the IAC valve to perform idle-up and
provide feedback for the target idling speed.
DTC No.DTC Detecting ConditionTrouble Area
P0505Idle speed continues to vary greatly from the target speed (2
trip detection logic)
Open or short in IAC valve circuit
IAC valve is stuck or closed
Open or short in A/C signal circuit
Air induction system
ECM
WIRING DIAGRAM
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.
DI083-09
Page 982 of 1897
A07628
ON
RSOE4 Connector
(+) (-)
- DIAGNOSTICSENGINE
DI-103
259 Author: Date:
2001 AVALON (RM808U)
1 Check idle speed.
When using TOYOTA hand-held tester:
PREPARATION:
(a) Warm up the engine to normal operating temperature.
(b) Switch off all the accessories.
(c) Switch off the A/C.
(d) Shift transmission into the N range or neutral position.
(e) Connect the TOYOTA hand-held tester to the DLC3 on the vehicle and select the ACTIVE TEST
mode.
CHECK:
Check the difference of the engine speed between the ones, less than 5 sec. and more than 5 sec. after
switching the TE1 from OFF to ON by the TOYOTA hand-held tester.
OK:
Difference of engine speed: More than 100 rpm
When not using TOYOTA hand-held tester:
PREPARATION:
(a) Warm up the engine to normal operating temperature.
(b) Switch off all the accessories.
(c) Switch off the A/C.
(d) Shift transmission into the N range or neutral position.
(e) Connect the OBDII scan tool to DLC3 on the vehicle.
(f) Using SST, connect terminals TE1 and E1 of the DLC1.
SST 09843-18020
CHECK:
Check the difference of engine speed between the ones, less than 5 sec. and more than 5 sec. after connect-
ing terminals TE1 and E1 of the DLC1.
OK:
Difference of engine speed: More than 100 rpm
OK Go to step 6.
NG
2 Check voltage between terminal RSO of ECM connector and body ground.
PREPARATION:
(a) Remove the glove compartment (See page SF-83).
(b) Disconnect the E4 connector from the ECM.
(c) Turn the ignition switch ON.
CHECK:
Measure the voltage between terminal RSO of the ECM con-
nector and body ground.
OK:
Voltage: 9 - 14 V
Page 983 of 1897
DI-104
- DIAGNOSTICSENGINE
260 Author: Date:
2001 AVALON (RM808U)
OK Go to step 4.
NG
3 Check IAC valve (See page SF-43).
NG Replace IAC valve.
OK
Check for open and short in harness and connector between engine room J/B and IAC valve, and
IAC valve and ECM (See page IN-30).
4 Check operation of IAC valve (See page SF-46).
NG Repair or replace IAC valve.
OK
5 Check blockage of IAC valve and passage to bypass throttle valve.
NG Repair or replace IAC valve.
OK
Check and replace ECM (See page IN-30).
6 Check for A/C signal circuit (See page DI-824).
NG Repair or replace.
Page 984 of 1897
- DIAGNOSTICSENGINE
DI-105
261 Author: Date:
2001 AVALON (RM808U)
OK
Check air induction system
(See page SF-1).
Page 985 of 1897
DI-106
- DIAGNOSTICSENGINE
262 Author: Date:
2001 AVALON (RM808U)
DTC P1130 A/F Sensor Circuit Range/Performance Mal-
function (Bank 1 Sensor 1)
DTC P1150 A/F Sensor Circuit Range/Performance Mal-
function (Bank 2 Sensor 1)
CIRCUIT DESCRIPTION
Refer to DTC P0125 on page DI-43.
DTC No.DTC Detecting ConditionTrouble Area
Voltage output* of A/F sensor remains at 3.8 V or more, or 2.8
V or less, during engine running after the engine is warmed up
(2 trip detection logic)
*: Output value changes at inside of ECM only
Open or short in A/F sensor circuit
A/F sensor
P1130
P1150Voltage output* of A/F sensor does not change from 3.30 V,
during engine running after the engine is warmed up (2 trip
detection logic)
*: Output value changes at the inside of ECM onlyAir induction system
Fuel pressure
Injector
ECM
Open or short in A/F sensor circuit (2 trip detection logic)
HINT:
After confirming DTC P1130, use the OBD II scan tool or TOYOTA hand-held tester to confirm voltage
output of A/F sensor (AFS B1 S1/O2S B1 S1) from the CURRENT DATA.
The A/F sensor's output voltage and the short-term fuel trim value can be read using the OBD II scan
tool or TOYOTA hand-held tester.
The ECM controls the voltage of the AFR+, AFL+, AFR- and AFL- terminals of the ECM to the fixed
voltage. Therefore, it is impossible to confirm the A/F sensor output voltage without the OBDII scan
tool or TOYOTA hand-held tester.
OBD II scan tool (excluding TOYOTA hand-held tester) displays the one fifth of the A/F sensor output
voltage which is displayed on the TOYOTA hand-held tester.
WIRING DIAGRAM
Refer to DTC P0125 on page DI-43.
DI2H7-03
Page 986 of 1897
A00364
Vehicle Speed
60 - 120 km/h
(38 - 75 mph)
Idling
IG SW OFF
3 - 5 min.
Time
(a) (b)(c)(d)
- DIAGNOSTICSENGINE
DI-107
263 Author: Date:
2001 AVALON (RM808U)
CONFIRMATION DRIVING PATTERN
(a) Connect the TOYOTA hand-held tester to the DLC3.
(b) Switch the TOYOTA hand-held tester from the normal mode to the check mode (See page DI-3).
(c) Start the engine and warm it up with all the accessory switches OFF.
(d) Drive the vehicle at 60 - 120 km/h (38 - 75 mph) and engine speed at 1,400 - 3,200 rpm for 3 - 5 min.
HINT:
If a malfunction exists, the MIL will light up during step (d).
NOTICE:
If the conditions in this test are not strictly followed, detection of the malfunction will not be possible.
If you do not have a TOYOTA hand-held tester, turn the ignition switch OFF after performing steps
(c) and (d), then perform steps (c) and (d) again.
INSPECTION PROCEDURE
HINT:
If DTC P1130 is displayed, check Bank 1 Sensor 1 circuit.
If DTC P1150 is displayed, check Bank 2 Sensor 1 circuit.
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 P1130, P1150) being output?
YES Go to relevant DTC chart (See page DI-14).
NO
Page 987 of 1897
DI-108
- DIAGNOSTICSENGINE
264 Author: Date:
2001 AVALON (RM808U)
2 Check output voltage of A/F sensor.
PREPARATION:
(a) Connect the OBD II scan tool or TOYOTA hand-held tester to the DLC3.
(b) Warm up the A/F sensor with the engine speed at 2,500 rpm for approx. 90 sec.
CHECK:
Read the voltage value of the A/F sensor on the screen of OBDII scan tool or TOYOTA hand-held tester
when you perform all the following conditions.
HINT:
The voltage of the AFR+ or AFL+ terminal of the ECM is fixed at 3.3 V and the voltage of the AFR- or AFL-
terminal is fixed at 3.0 V. Therefore, it is impossible to check the A/F sensor output voltage at the terminals
(AFR+, AFL+/AFR-, AFL-) of the ECM.
OK:
ConditionA/F Sensor Voltage Value
Engine idling
Engine racingNot remains at 3.30 V (0.660 V*)
Not remains at38V(076V*) or moreDriving at engine speed 1,500 rpm or more and vehicle
speed 40 km/h (25 mph) or more, and operate throttle valve
open and closeNot remains at 3.8 V (0.76 V*) or more
Not remains at 2.8 V (0.56 V*) or less
*: When you use OBD II scan tool (excluding TOYOTA hand-held tester)
HINT:
During fuel enrichment, there is a case that the output voltage of the A/F sensor is below 2.8 V (0.56
V*), it is normal.
During fuel cut, there is a case that the output voltage of the A/F sensor is above 3.8 V (0.76 V*), it
is normally.
If the output voltage of the A/F sensor remains at 3.30 V (0.660 V*) even after performing all the above
conditions, the A/F sensor circuit may be open.
If the output voltage of the A/F sensor remains at 3.8 V (0.76 V*) or more, or 2.8 V (0.56 V*) or less
even after performing all the above conditions, the A/F sensor circuit may be short.
*: When you use the OBD II scan tool (excluding TOYOTA hand-held tester).
OK Go to step 9.
NG
3 Check for open and short in harness and connector between ECM and A/F sen-
sor (See page IN-30).
NG Repair or replace harness or connector.
OK
Page 988 of 1897
- DIAGNOSTICSENGINE
DI-109
265 Author: Date:
2001 AVALON (RM808U)
4 Check resistance of A/F sensor heater (See page SF-79).
NG Replace A/F sensor.
OK
5 Check air induction system (See page SF-1).
NG Repair or replace.
OK
6 Check fuel pressure (See page SF-6).
NG Check and repair fuel pump, pressure regulator,
fuel pipe line and filter (See page SF-1).
OK
7 Check injector injection (See page SF-23).
NG Replace injector.
OK
Replace A/F sensor.
8 Perform confirmation driving pattern (See page DI-106).
Go
Page 989 of 1897
DI-1 10
- DIAGNOSTICSENGINE
266 Author: Date:
2001 AVALON (RM808U)
9 Is there DTC P1130 or P1150 being output again?
YES Check and replace ECM (See page IN-30).
NO
10 Did vehicle runs out of fuel in past?
NO Check for intermittent problems (See page
DI-3).
YES
DTC P1130 or P1150 is caused by running out
of fuel.
Page 990 of 1897
- DIAGNOSTICSENGINE
DI-1 11
267 Author: Date:
2001 AVALON (RM808U)
DTC P1133 A/F Sensor Circuit Response Malfunction
(Bank 1 Sensor 1)
DTC P1153 A/F Sensor Circuit Response Malfunction
(Bank 2 Sensor 1)
CIRCUIT DESCRIPTION
Refer to DTC P0125 on page DI-43.
DTC No.DTC Detecting ConditionTrouble Area
P1133
P1153
After engine is warmed up, and during vehicle driving at engine
speed 1,400 rpm or more and vehicle speed 60 km/h (38 mph)
or more, if the response characteristic of A/F sensor becomes
deteriorated (2 trip detection logic)
Open or short in A/F sensor circuit
A/F sensor
Air induction system
Fuel pressure
Injector
ECM
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 P1133, P1153) being output?
YES Go to relevant DTC chart (See page DI-14).
NO
2 Connect OBDII scan tool or TOYOTA hand-held tester, and read value for volt-
age output of A/F sensor.
PREPARATION:
(a) Connect the OBD II scan tool or TOYOTA hand-held tester to the DLC3.
(b) Warm up the A/F sensor with the engine speed at 2,500 rpm for approx. 90 sec.
CHECK:
Read the voltage of the A/F sensor on the screen of the OBD II scan tool or TOYOTA hand-held tester when
you perform all the following conditions.
DI2H8-03