2001 TOYOTA AVALON Service Repair Manual

F07898
1314
- DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
DI-307
463 Author
: Date
:
2001 AVALON (RM808U)
INSPECTION PROCEDURE
1 Check operation of brake actuator pump motor.
PREPARATION:
Disconnect the connector from the brake actuator.
CHECK:
Connect positive
lead to terminal 14 and negative  lead to
terminal 13 of the brake actuator connector, check that the
pump motor is operated.
OK:
The running sound of the pump motor should be
heard.
OK Check for open circuit in harness and connec-
tor between ABS motor relay, brake actuator
and ECU (See page IN-30).
NG
Replace brake actuator.

F09810
ABS & BA &
TRAC & VSC ECU
ML- ML+
A622
24
A20 A20
IE1 Precharge Pump
V
VW-R
W-R
IE18
9 A61
6
ML- ML+
ML- ML+ Brake Actuator
1 2 DI-308
- DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
464 Author
: Date
:
2001 AVALON (RM808U)
DTC C1351 / 52Precharge Pump Motor Circuit
CIRCUIT DESCRIPTION
DTC No.DTC Detecting ConditionTrouble Area
C1351 / 52
When any of the following 1. or 2. is detected:
1. After the ignition switch is turned ON, an open or short
circuit continues for 0.06 sec. or more.
2. The precharge pump motor voltage is out of range when
precharge pump if off.

Precharge pump motor

Precharge pump motor circuit
WIRING DIAGRAM
DI6OB-02

F07901
2 1
(-)(+)
- DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
DI-309
465 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 TOYOTA hand-held tester.
1 Check precharge pump motor operation.
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 the operation sound of the precharge pump motor when operating it with the TOYOTA hand-held
tester.
OK:
The operation sound of the precharge pump motor should be heard.
NG Go to step 3.
OK
If the same code is still output after the DTC is deleted, check the contact condition of each con-
nection. If the connections are normal, the ECU may be defective.
2 Check precharge pump motor operation.
PREPARATION:
Disconnect the connector from the precharge pump motor.
CHECK:
Connect ML+ (2) terminal to the battery positive (+) and ML- (1)
terminal to the battery negative (-).
OK:
The operation sound of the pump motor should be
heard.
NG Check and replace precharge pump.
OK

DI-310
- DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
466 Author
: Date
:
2001 AVALON (RM808U)
3 Check for open and short circuit in harness and connector between precharge
pump and ABS & BA & TRAC & VSC ECU (See page IN-30).
NG Repair or replace harness and connector.
OK
Check and replace ABS & BA & TRAC & VSC
ECU.

F09809
59
W
A20
SS1 ABS & BA & TRAC
& VSC ECU
61
A20
SS2
60
A20
FSS BR
(Shielded) Translate ECU
O 4
T5
17
T5 VSC+
VSC-
- DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
DI-31 1
467 Author
: Date
:
2001 AVALON (RM808U)
DTC 42 ECU Communication System Malfunction
CIRCUIT DESCRIPTION
The circuit is used to send TRAC & VSC control information from ABS & BA & TRAC & VSC ECU to the
translate ECU (VSC+, VSC-), engine control information and steering angle information from translate ECU
to ABS & BA & TRAC & VSC ECU
DTC No.DTC Detecting ConditionTrouble Area
42IG1 voltage is 9.5 V or more, and the condition that data
from ECU can not be received continues for 5 sec. or more.
VSC+ or VSC- circuit

Translate ECU

ABS & BA & TRAC & VSC ECU
WIRING DIAGRAM
DI6OC-03

F10171
Normal Signal Waveform
2 m/s / DivisionGND
1 V / Division
DI-312
- DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
468 Author
: Date
:
2001 AVALON (RM808U)
INSPECTION PROCEDURE
1 Check DTC of translate ECU.
Check DTC on page DI-252.
*1 Repair circuit indicated by the output code.
*2
2 Check transrate ECU communication.
REFERENCE: INSPECTION USING OSCILLOSCOPE
PREPARATION:
(a) Remove the translate ECU.
(b) Connect the oscilloscope to the terminal VSC+ (4) and
GND (14) of the translate ECU harness side connector.
CHECK:
Start the engine, and check the signal waveform.
OK Check and replace ABS & BA & TRAC & VSC
ECU.
NG
3 Check for open and short circuit in harness and connector between each of ter-
minals VSC+ and VSC- of translate ECU and ABS & BA & TRAC & VSC ECU (See
page IN-30).
NG Repair or replace harness or connector.
OK
Check and replace ABS & BA & TRAC & VSC
ECU.
*1: Output NG code
*2: Output nomal code

F09807
Translate ECU
13
T5 ECM
NEO
NEO16
E7Y-B
- DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
DI-313
469 Author
: Date
:
2001 AVALON (RM808U)
DTC 44 NEO Signal Circuit
CIRCUIT DESCRIPTION
The ABS & BA & TRAC & VSC ECU receives engine revolution speed signals (NEO signal) from the ECM.
DTC No.DTC Detecting ConditionTrouble Area
44
When either of the following 1. or 2. is detected:
1. The vehicle speed is 30 km/h (19 mph) or more, and
open or short condition of the engine revolution signal
under the normal communication condition with ECU
continues for 10 secs. or more.
2. While cancel of cruise control is instructed from VSC
ECU, open or short condition of the engine revolution
signal continues for 0.24 sec. or more.

NEO circuit

ECM

Translate ECU
WIRING DIAGRAM
DI6OD-03

F09477
ON
NEO
13
F03007
(Reference)
3 - 6 V
Below 1 V
DI-314
- DIAGNOSTICSABS WITH EBD & BA & TRAC & VSC SYSTEM
470 Author
: Date
:
2001 AVALON (RM808U)
INSPECTION PROCEDURE
1 Check for open and short circuit in harness and connector between terminal
NEO of translate ECU and terminal NEO of ECM (See page IN-30).
NG Repair or replace harness and connector.
OK
2 Check voltage between terminal NEO (13) of translate ECU and body ground.
PREPARATION:
Remove the translate ECU with connectors still connected.
CHECK:
(a) Turn the ignition switch ON.
(b) Measure the voltage between terminal 13 of the translate
ECU and body ground under the engine conditions below.
OK:
Engine conditionVoltage
OFF (IG ON)3 - 6 V or below 1 V
ON (Idling)3 - 6 V e below 1 V (Pulse)
NG Check and replace ECM.
OK
Check and replace transrate ECU.
If the same code is still output after the DTC is deleted, check the contact condition of each con-
nection.