2001 TOYOTA AVALON Service Repair Manual

F09815
ECM
TRC- G-W
BRTranslate ECU
7
T5
TRC+ 20
T5
ENG- 9
T5
ENG+ 22
T5 GR
V TRC-
TRC+
ENG-
ENG+20
E8
13
E8
21
E8
14
E8
- DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
DI-315
471 Author
: Date
:
2001 AVALON (RM808U)
DTC 53 ECM Communication Circuit Malfunction
CIRCUIT DESCRIPTION
The circuit is used to send TRAC & VSC control information from the translate ECU to the ECM (TRC+,
TRC-), and engine control information from the ECM to the translate ECU (ENG+, ENG-).
DTC No.DTC Detecting ConditionTrouble Area
53
When any of the following 1. through 3. is detected :
1. IG1 voltage is 8.5 V or more, and the condition that data
can not be sent to ECM continues for 5 sec. or more.
2. IG1 voltage is 8.5 V or more, engine speed is 500 r.p.m
or more, and the condition that data can not be received
from ECM continues for 5 sec. or more.
3. The condition that data can not be transmitted between
the translate ECU and ECM occurs at least once within
5 sec. continues 10 consecutive times.

TRC+ or TRC- circuit

ENG+ or ENG- circuit

ECM

Translate ECU
WIRING DIAGRAM
DI6OE-03

F10171
Normal Signal Waveform
2 m/s / DivisionGND
1 V / Division
DI-316
- DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
472 Author
: Date
:
2001 AVALON (RM808U)
INSPECTION PROCEDURE
1 Check translate ECU communication.
REFERENCE: INSPECTION USING OSCILLOSCOPE
PREPARATION:
(a) Remove the translate ECU.
(b) Connect the oscilloscope to each of the terminals ENG+
or TRC+ and GND of the translate ECU harness side con-
nector.
CHECK:
Start the engine, and check the signal waveform.
OK Check and replace translate ECU.
NG
2 Check for open and short circuit in harness and connector between each of ter-
minals ENG+, ENG-, TRC+ and TRC- of translate ECU and ECM (See page
IN-30).
NG Repair or replace harness or connector.
OK
Check and replace ECM.

F07889
DI-346
- DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
502 Author
: Date
:
2001 AVALON (RM808U)
Check for Fluid Leakage
Check for fluid leakage from actuator or hydraulic lines.
DI6OQ-01

DI-318
- DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
474 Author
: Date
:
2001 AVALON (RM808U)
DTC Non Code Translate ECU Malfunction
CIRCUIT DESCRIPTION
DTC No.DTC Detecting ConditionTrouble Area
Non CodeTranslate ECU internal malfunction is detected.

Tc terminal circuit

Brake warning light circuit

Translate ECU
INSPECTION PROCEDURE
1 Check the BRAKE warning light circuit (See page DI-330).
NG Repair or replace the BRAKE warning light cir-
cuit.
OK
2 Check the Tc terminal circuit (See page DI-342).
NG Repair or replace the Tc terminal circuit.
OK
Check and replace Translate ECU.
DI6OF-04

- DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
DI-317
473 Author
: Date
:
2001 AVALON (RM808U)
DTC Normal Code Malfunction in ECM
CIRCUIT DESCRIPTION
If any trouble occurs in the ECM control system, the ECU prohibits ABS & VSC control.
DTC No.DTC Detecting ConditionTrouble Area
Normal Code
Conditions 1., 2,. 3, or 4,continue for 5 sec. or more:
1. Engine malfunction signal is sent from ECM.
2. Shift malfunction signal is sent from ECM
3. The shift position is other than P and N range input volt-
age is 8 V or more.
4. The shift position is PN or rev and D range input voltage
is 8 V or more.
ECM circuit

ECM

Brake fluid level

Brake fluid level warning switch circuit

Steering angle sensor

ABS & BA & TRAC & VSC ECU
INSPECTION PROCEDURE
1 Is DTC out put for ECM?
Check DTC on page DI-3.
YES Repair engine control system according to the
output code.
NO
2 Check the DTC for the ABS and VSC (See page DI-252).
*1 Repair ABS and VSC control system according
to the code output.
*2
Check and replace translate ECU.
*1: Output NG code except for DTC of VSC system C1301/42
*2: Output NG code DTC of VSC system C1301/42 only
DI6OF-03

F09822
ABS & BA &
TRAC & VSC ECU
IND A2031
V V18
IL1 M6 M69
4SLIP
R-B J/B No. 4
4D
4F 413
R-B
Driver Side J/B
1G1
1D10
1B1C 3 41 2IG1 Relay GAUGE
No. 1
W
W-R
2
IG1
AM1 4Ignition Switch
IF17
W-L
551
2 AM1 Engine Room R/B No. 5
B
2G
2H1 1 Engine Room J/B
B-L
F6 1 F10 F81
1
ALT FL Block
IG
Battery
FL MAIN
B Multi Display
4 3
W-BW-L
- DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
DI-333
489 Author
: Date
:
2001 AVALON (RM808U)
SLIP Indicator Light Circuit
CIRCUIT DESCRIPTION
The SLIP indicator light blinks during TRAC & VSC operation.
WIRING DIAGRAM
DI6OL-03

DI-334
- DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
490 Author
: Date
:
2001 AVALON (RM808U)
INSPECTION PROCEDURE
HINT:
Start the inspection from step 1, in case of using the TOYOTA hand-held tester and start from step 2, in case
of not using the TOYOTA hand-held tester.
1 Check operation of the SLIP indicator light.
PREPARATION:
(a) Connect the TOYOTA hand-held tester to the DLC3.
(b) Turn the ignition switch ON and push the TOYOTA hand-held tester main switch ON.
(c) Select the ACTIVE TEST mode on the TOYOTA hand-held tester.
CHECK:
Check that ºONº and ºOFFº of the SLIP indicator light can be shown on the combination meter with the TOY-
OTA hand-held tester.
OK Go to step 4.
NG
2 Check that the SLIP indicator light is ON for 3 seconds immediately after ignition
switch is turned ON.
OK Check and replace ABS & BA & TRAC & VSC
ECU.
NG
3 Check SLIP indicator light.
See combination meter troubleshooting on page BE-2.
NG Repair or replace combination meter. Check
and replace ABS & BA & TRAC & VSC ECU.
OK

- DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
DI-335
491 Author
: Date
:
2001 AVALON (RM808U)
4 Check for open and short circuit in harness and connector between ABS & BA
TRAC & VSC ECU and SLIP indicator light (See page IN-30).
NG Repair or replace harness or connector.
OK
Check and replace ABS & BA & TRAC & VSC
ECU.