2001 TOYOTA AVALON ignition

N09214
- DIAGNOSTICSAUTOMATIC TRANSAXLE
DI-161
317 Author
: Date
:
2001 AVALON (RM808U)

The diagnosis system operates in normal mode
during normal vehicle use, and also has a check
mode for technicians to simulate malfunction symp-
toms and perform troubleshooting. Most DTCs use
2-trip detection logic(*) to prevent erroneous detec-
tion. By switching the ECM to check mode when
troubleshooting, the technician can cause the MIL
to light up and for a malfunction that is only detected
once or momentarily (TOYOTA hand-held tester)
(See page DI-160).

*2-trip detection logic:
When a logic malfunction is first detected, the mal-
function is temporarily stored in the ECM memory.
If the same malfunction is detected again during the
2nd test drive, this 2nd detection causes the MIL to
light up.
(b) Inspect the DLC3.
The vehicle's ECM uses ISO 9141-2 for communication.
The terminal arrangement of DLC3 complies with SAE
J1962 and matches the ISO 9141-2 format.
Tester connectionConditionSpecified condition
7 (Bus
Line) - 5 (Signal ground)During communicationPulse generation
4 (Chassis Ground) - BodyAlways1 W or less
5 (Signal Ground) - BodyAlways1 W or less
16 (B+) - BodyAlways9 - 14 V
HINT:
If your display shows ºUNABLE TO CONNECT TO VEHICLEº
when you have connected the cable of OBD II scan tool or TOY-
OTA hand-held tester to DLC3, turned the ignition switch ON
and operated the scan tool, there is a problem on the vehicle
side or tool side.

If communication is normal when the tool is connected to
another vehicle, inspect DLC3 on the original vehicle.

If communication is still not possible when the tool is con-
nected to another vehicle, the problem is probably in the
tool itself, so consult the Service Department listed in the
tool's instruction manual.

FI0534
F07887
TOYOTA hand-held tester
DLC3
DI-162
- DIAGNOSTICSAUTOMATIC TRANSAXLE
318 Author
: Date
:
2001 AVALON (RM808U)
2. INSPECT DIAGNOSIS (NORMAL MODE)
(a) Check the MIL.
(1) The MIL comes on when the ignition switch is turned
ON and the engine is not running.
HINT:
If the MIL does not light up, troubleshoot the combination meter
(See page BE-2).
(2) When the engine is started, the MIL should go off.
If the lamp remains on, the diagnosis system has
detected a malfunction or abnormality in the sys-
tem.
(b) Check the DTC.
NOTICE:
TOYOTA hand-held tester only:
When the diagnostic system is switched from normal mode
to check mode, it erases all DTCs and freeze frame data re-
corded in normal mode. So before switching modes, al-
ways check the DTCs and freeze frame data, and note them
down.
(1) Prepare an OBD II scan tool (complying with SAE
J1978) or TOYOTA hand-held tester.
(2) Connect the OBD II scan tool or TOYOTA hand-
held tester to DLC3 at the lower of the instrument
panel.
(3) Turn the ignition switch ON and turn the OBD II scan
tool or TOYOTA hand-held tester switch ON.
(4) Use the OBD II scan tool or TOYOTA hand-held
tester to check the DTCs and freeze frame data and
note them down (For operating instructions, see the
OBD II scan tool's instruction book).
(5) See page DI-172 to confirm the details of the DTCs.
NOTICE:
When simulating symptoms with an OBD II scan tool (ex-
cluding TOYOTA hand-held tester) to check the DTCs, use
normal mode. For codes on the DTCs chart subject to
º2-trip detection logicº, turn the ignition switch OFF after
the symptoms have been simulated the 1st time. Then re-
peat the simulation process again. When the program has
DTCs they are recorded in the ECM.

F07887
TOYOTA hand-held tester
DLC3
BR3904
0.13 sec. 0.13 sec.
ON
OFF
- DIAGNOSTICSAUTOMATIC TRANSAXLE
DI-163
319 Author
: Date
:
2001 AVALON (RM808U)
3. INSPECT DIAGNOSIS (CHECK MODE)
HINT:
TOYOTA hand- held tester only: Compared to the normal
mode, the check mode has high sensing ability to detect mal-
functions. Furthermore, the same diagnostic items which are
detected in Normal mode can also be detected in Check mode.
(a) Check the DTC.
(1) Check the initial conditions.

Battery positive voltage 11 V or more

Throttle valve fully closed

Transaxle in P position

Air conditioning switched OFF
(2) Turn the ignition switch OFF
(3) Prepare a TOYOTA hand-held tester
(4) Connect the TOYOTA hand-held tester to DLC3 at
the lower of the instrument panel.
(5) Turn the ignition switch ON and switch the TOYOTA
hand-held tester ON.
(6) Switch the TOYOTA hand-held tester from Normal
mode to Check mode (Check that the MIL flashes).
(7) Start the engine (MIL goes out after the engine
starts).
(8) Simulate the conditions of the malfunction de-
scribed by the customer.
NOTICE:
Leave the ignition switch ON until you have checked the
DTCs, etc..
(9) After simulating the malfunction conditions, use the
TOYOTA hand-held tester diagnosis selector to
check the DTCs and freeze frame data, etc.
HINT:
Take care not to turn the ignition switch OFF, as turning it off
switches the diagnosis system from Check mode to Normal
mode, so all DTCs, etc. are erased.
(10) After checking the DTC, inspect the applicable cir-
cuit.

AB0119N09214
I11292
ON
DLC3
- DIAGNOSTICSBODY CONTROL SYSTEM
DI-667
823 Author
: Date
:
2001 AVALON (RM808U)
INSPECTION PROCEDURE
1 Check voltage between terminals Tc and E1 of DLC3.
PREPARATION:
Turn ignition switch ON.
CHECK:
Measure voltage between terminals SIL(7) and CG(4) of DLC3.
OK:
Voltage: 10 - 14 V
OK Proceed to next circuit inspection shown in
problem symptom table (See page DI-622).
NG
2 Check harness and connector between body control ECU and DLC3, DLC3 and
body ground (See page IN-30).
NG Repair or replace harness or connector.
OK
Check and replace Body Control ECU
(See page IN-30).

- DIAGNOSTICSBODY CONTROL SYSTEM
DI-655
811 Author
: Date
:
2001 AVALON (RM808U)
Illumination circuit
CIRCUIT DESCRIPTION
Receiving the courtesy signal from either of the door ECU, the Body ECU will make the interior light, ignition
light, and foot light come on.
DI6LX-01

I13641
P-LP-LP-LP-L
P-L
P-L
P-L 1
4F
4D
4C 11
7
1D 1J9 DOME
W-L
1
11 1
1
12C DCC
2
2G
B
F7 F6FL Block
FL MAINB
BatteryV11
Vanity Light RH
2
V10
Vanity Light RH
2W-B
W-B
2
3P9
Personal Light
ON
OFF
DOOR
I17
Interior Light
ON
OFF
DOOR
4
4D
R-B13
4F
R-BG-R
G-R3
1C5
ILL
10
1D2 GAUGE No. 1IG1 RELAY
11
4
3 4
1C 1B3 1GMulti Display
3
42
2 M7
M6M7
M6 Open Door
Driver Seat Belt
10
M7R
G-W
G-R25
B5
B5
B523
11AJAR
DBEW
PBEW
FL MAIN FL Block
ALT W
1
F101
F6
F81B
B-L
Battery
11
2H 2G W-B W-R
4
IG1 AM1 I15
Ignition Switch
2
W-L7
IF1
IG
AM1
21
55W-L
B2BLBody ECU
IG1 5
G-R
IG1
G-R 11 4C10
P-L
2
1
I14
Ignition
Key
Cylinder
LightG-R Engine Room J/B
Engine Room R/B No.5Engine Room J/B J/B No.4
Driver Side J/B
Passenger
Seat Belt
Driver Side J/B J/B No.4
Driver Side J/B
8W-B
1
G-R
IG1
DI-656
- DIAGNOSTICSBODY CONTROL SYSTEM
812 Author
: Date
:
2001 AVALON (RM808U)
WIRING DIAGRAM

I13648
9Key Unlock
Warning Switch
17
B4Body ECU
KSW
R-Y 11
4A 4B2
R-Y W-B12 U1
3D 22
3D
W-B
IGJ/B No. 3 J/B No. 4
- DIAGNOSTICSBODY CONTROL SYSTEM
DI-637
793 Author
: Date
:
2001 AVALON (RM808U)
Key unlock warning switch circuit
CIRCUIT DESCRIPTION
The key unlock warning switch goes on when the ignition key is inserted in the key cylinder and goes off when
the ignition key is removed.
The ECU operates the key confinement prevention function while the key unlock warning switch is on.
WIRING DIAGRAM
DI6LO-01

I13659
P1
Park/Neutral
Position Switch
2PL7
G-W3
II2
G-W18 18
3A 3H
G-W1
B4Body ECU
R-L 20
3D
3C20 7
3C R-L D6
Diode
A/T Indicator Light
3 2
R-Y
*2
*1
R-L R-L
20
II1
11
1C
1B3 GAUGE No. 2
12
34 4IG1 RELAY
1C 1G
W
W-R
4Ignition Switch
IG1
AM1
2
W-LW-L 7
IF1 5 5AM1
21
BW-B
1
2H
2G1
B-L 1
F8 FL Block
1
F10
F61
BALT
FL MAINBattery
IGP
*1: FLOOR SHIFT
*2: COLUMN SHIFTJ/B No. 3
J/B No. 3
Driver Side J/B
J/B No. 5
Engine Room J/B
*2
I15 DI-664
- DIAGNOSTICSBODY CONTROL SYSTEM
820 Author
: Date
:
2001 AVALON (RM808U)
Park/Neutral Position Switch Circuit
CIRCUIT DESCRIPTION
The park/neutral position switch detects the shift lever p position and sends signals to the Body ECU.
WIRING DIAGRAM
DI6M1-01