2001 TOYOTA AVALON Service Repair Manual

N21467
N21465
N21466
I00528
Front Vertical Motor
Reclining Motor Rear Vertical Motor21
21
21
21
21
21
DI-502- DIAGNOSTICSPOWER SEAT CONTROL SYSTEM (w/ Driving Position
Memory)
658 Author
: Date
:
2001 AVALON (RM808U)
Front Vertical Motor
CHECK:
Connect battery
to terminal 2 and battery  to terminal 1 of
the front vertical motor connector.
OK:
The front of the seat cushion rises.
CHECK:
Connect battery  to terminal 2 and battery
to terminal 1 of
the front vertical motor connector.
OK:
The front of the seat cushion lowers.
Rear Vertical Motor
CHECK:
Connect battery
to terminal 2 and battery  to terminal 1 of
the rear vertical motor connector.
OK:
The front of the seat cushion rises.
CHECK:
Connect battery  to terminal 2 and battery
to terminal 1 of
the rear vertical motor connector.
OK:
The front of the seat cushion lowers.
Reclining Motor
CHECK:
Connect battery
to terminal 2 and battery  to terminal 1 of
the reclining motor connector.
OK:
The seat back returns to up right.
CHECK:
Connect battery  to terminal 2 and battery
to terminal 1 of
the reclining motor connector.
OK:
The seat back is reclining.
NG Replace motor.
OK

- DIAGNOSTICSPOWER SEAT CONTROL SYSTEM (w/ Driving Position
Memory)DI-503
659 Author
: Date
:
2001 AVALON (RM808U)
2 Check harness and connector between Seat Position Control ECU and motor
(See page DI-489).
NG Repair or replace harness or connector.
OK
Proceed to next circuit inspection shown on
problem symptom table (See page DI-493).

BE3991
1 pulse output per one
turn of motor
Position Sensor
(in Motor)8 V
0 V
ECU
N14754
Example: Slide Motor
Motor Sensor
(+)
2
(+) (-)
(-)1 31 2
DI-506- DIAGNOSTICSPOWER SEAT CONTROL SYSTEM (w/ Driving Position
Memory)
662 Author
: Date
:
2001 AVALON (RM808U)
Position Sensor Circuit
CIRCUIT DESCRIPTION
The position sensor senses movement of the seat and send
pulse signals to the ECU. The position sensor sends pulse to
the ECU in proportion to the amount of seat movement, as
shown in the diagram on the left.
The ECU uses the number of pulses to constantly calculate the
position relative to the memory position and returns the seat to
the memorized position.
If a malfunction occurs in a position sensor and a sensor signal
is not input to the ECU even when the motor operates, the ECU
prohibits return operation.
WIRING DIAGRAM
See page DI-504.
INSPECTION PROCEDURE
1 Check position sensor.
PREPARATION:
Disconnect the connector of the sensor and the connector of
the motor leading to the sensor.
CHECK:
(a) Connect positive
lead to terminal 3 of sensor and nega-
tive  lead to terminal 2.
(b) Measure voltage between terminal 1 of sensor and body
ground when battery positive voltage is applied between
terminals 1 and 2 of motor connector.
HINT:
When the battery positive voltage is applied to the motor con-
nector terminals,
and  are interchangeable.
OK:
ConditionVoltage
Motor stopped
(Check several times with the motor in a
different position each time.)0 V or battery positive voltage according
to stop position.
with motor turninghalf of battery positive voltage
NG Replace position sensor.
OK
DI0G9-08

- DIAGNOSTICSPOWER SEAT CONTROL SYSTEM (w/ Driving Position
Memory)DI-507
663 Author
: Date
:
2001 AVALON (RM808U)
2 Check harness and connectors between Seat Position Control ECU and position
sensors (See page IN-30).
NG Repair or replace harness or connectors.
OK
Check and replace Seat Position Control
ECU.

I13624
SSRR
PVCC
SSFV SSRS
SSRL L-BL
R
L-W53
4 16
17Power Seat ECU
1 2
1 2
1 2
1 2
3 3 3 3
BR
BR
BR B
BB B
BR J14
J/C
9
9
BR
BR A
AJ3
J/C
IHP21
P21
P21
P21
P21 L-R BR
P30
P29
P32
P31
Power Seat
Position Sensor
Reclining Control
Front Vertical Control
Rear Vertical Control Slide Control
IA1 BC1
BR
J/CJ14
A
A
A A R
R
R
R DI-504
- DIAGNOSTICSPOWER SEAT CONTROL SYSTEM (w/ Driving Position
Memory)
660 Author
: Date
:
2001 AVALON (RM808U)
Position Sensor Power Source Circuit
CIRCUIT DESCRIPTION
This circuit provides power to the slide, front vertical and reclining position sensors.
WIRING DIAGRAM
DI0G6-09

I11593
(+) (-)
5 (PVCC)
- DIAGNOSTICSPOWER SEAT CONTROL SYSTEM (w/ Driving Position
Memory)DI-505
661 Author
: Date
:
2001 AVALON (RM808U)
INSPECTION PROCEDURE
1 Check voltage between terminal PVCC of Seat Position Control ECU connector
and body ground.
PREPARATION:
Remove Seat Position Control ECU with connectors still con-
nected.
CHECK:
While operating the Power Seat Control Switch and moving the
seat, check voltage between terminal PVCC of Seat Position
Control ECU connector and body ground.
OK:
Voltage: 7.2 - 8.8 V
OK Proceed to next circuit inspection shown on
problem symptom table (See page DI-493).
NG
2 Check harness and connector connected to terminal PVCC of Seat Position Con-
trol ECU (See page IN-30).
CHECK:
Check for open or short in the harness and check connectors for the position sensor power source circuit
outlined in the diagram with a thick line (-).
NG Repair or replace harness or connector.
OK
Check and replace Seat Position Control
ECU.

I13623
Power Seat Switch
RCLR
BKJ11
J/C 8R-B
B-Y
R-W
R-YG
G-B
B
7 2
3
10
9 6 5
11B-R
W-B
A W-B W-B W-B 1
CC CRCLF
FDWN
FUP
SLDR
SLDF
LUP
LDWN
GND Power Seat ECU
P18
BC1P21
P21
P21
P21
P21
P21
P21
P21
P2112
10
24
23
8
6
22
11
7
J14
J/C DI-510
- DIAGNOSTICSPOWER SEAT CONTROL SYSTEM (w/ Driving Position
Memory)
666 Author
: Date
:
2001 AVALON (RM808U)
Power Seat Control Switch Circuit
CIRCUIT DESCRIPTION
When the power seat control switch is operated, a signal is sent from the power seat control switch to the
ECU and the ECU sends a signal to the motor to make it operate.
Even if a malfunction should occur with the position sensor and return operation is prohibited, manual opera-
tion will occur as normal.
WIRING DIAGRAM
DI0GG-06

I11594
(+)
(-)
12 (RLCR)
24 (FDWN)
23 (FUP)11 (LDWN) 10 (RCLF)
8 (SLDR)
6 (SLDF)
19 (SGND)
22 (LUP)
I04159
Lifter
Up
DownReclining
Front Vertical
Up
Down Front BackForward
Rear
- DIAGNOSTICSPOWER SEAT CONTROL SYSTEM (w/ Driving Position
Memory)DI-51 1
667 Author
: Date
:
2001 AVALON (RM808U)
INSPECTION PROCEDURE
1 Check voltage between each terminal of the Power Seat Control Switch and
SGND of Seat Position Control ECU connector.
PREPARATION:
Remove Seat Position Control ECU with connectors still con-
nected.
CHECK:
Measure voltage between each terminal of the Power Seat
Control Switch and SGND of Seat Position Control ECU con-
nector. (The illustration shows inspection of the reclining as an
example.)
OK:
At each terminal with switch ON0 V
At each terminal with switch OFF10 ~ 14 V
OK Proceed to next circuit inspection shown in
problem symptom table (See page DI-493).
NG
2 Check power seat control switch.
PREPARATION:
(a) Remove seat.
(b) Disconnect power seat control switch.
CHECK:
Check continuity between terminals when switch operated.
OK:
Driver 's seat slide switch:
Switch positionTester connectionSpecified condition
FRONT1 - 9Continuity
BACK1 - 6Continuity
Driver 's seat front vertical switch:
Switch positionTester connectionSpecified condition
UP1 - 5Continuity
DOWN1 - 10Continuity
Driver 's seat lifter switch:
Switch positionTester connectionSpecified condition
UP1 - 8Continuity
DOWN1 - 7Continuity