Page 1721 of 4323
I27717
± DIAGNOSTICSPOWER SEAT CONTROL SYSTEM (w/ Driving Position
Memory)DI±1519
1713 Author: Date:
2005 SEQUOIA (RM1146U)
INSPECTION PROCEDURE
1 Inspect seat memory switch.
PREPARATION:
Disconnect the seat memory switch connector.
CHECK:
Measure the resistance of each terminal, as shown in the il-
lustration and table.
OK:
Tester ConnectionSwitch PositionSpecified Condition
1 ± 4SET switch OFF " ON10 kW or higher"
Below 1 W
2 ± 4Memory switch 1 OFF "
ON10 kW or higher"
Below 1 W
3 ± 4Memory switch 2 OFF "
ON10 kW or higher"
Below 1 W
NG Replace seat memory switch.
OK
Page 1722 of 4323
I27700
B6
Body ECU Wire Harness View:
MM
M1M2
DI±1520± DIAGNOSTICSPOWER SEAT CONTROL SYSTEM (w/ Driving Position
Memory)
1714 Author: Date:
2005 SEQUOIA (RM1146U)
2 Check harness and connector (Body ECU & seat memory switch ± body ground).
PREPARATION:
(a) Reconnect the seat memory switch connector.
(b) Disconnect the B6 body ECU connector.
CHECK:
Measure the resistance of each terminal, as shown in the il-
lustration and table.
OK:
Tester Connection
(Symbol)Switch PositionSpecified Condition
B6±23 (M1) ±
Body groundMemory switch 1 OFF "
ON10 kW or higher"
Below 1 W
B6±24 (MM) ±
Body groundSET switch OFF " ON10 kW or higher"
Below 1 W
B6±22 (M2) ±
Body groundMemory switch 2 OFF "
ON10 kW or higher"
Below 1 W
NG Repair or replace harness or connector.
OK
Proceed to next circuit inspection shown in
problem symptoms table (See page
DI±1508).
Page 1723 of 4323
I28448
PWR SEAT Instrument Panel J/B
ALT 161
1 2L±O L±O
BI29L4
Lumbar Support Control
Switch (Driver's Seat)
3 1 2
4
5 Rear Front
W
W±B W±B
BH BatteryLR1 L A
A
BI2 1G
1L
F10
FL BlockJ24 J/C
L3
Lumbar Support
Control Motor L±O
J24 J/C J/C
L±O
J31 J323
R B
H
B58C
G
BBB 2
W±B W±BE2E
± DIAGNOSTICSPOWER SEAT CONTROL SYSTEM (w/ Driving Position
Memory)DI±1521
1715 Author: Date:
2005 SEQUOIA (RM1146U)
Lumbar support control switch circuit
CIRCUIT DESCRIPTION
The lumbar support control switch that controls lumbar support is connected to the lumbar support control
motor via a wire harness. This circuit can freely operate regardless of the condition of the ECU.
WIRING DIAGRAM
DIDE9±01
Page 1724 of 4323
I28700
HOLD (Front)RELEASE (Rear)
DI±1522± DIAGNOSTICSPOWER SEAT CONTROL SYSTEM (w/ Driving Position
Memory)
1716 Author: Date:
2005 SEQUOIA (RM1146U)
INSPECTION PROCEDURE
1 Check fuse (PWR SEAT).
PREPARATION:
Remove the PWR SEAT fuse from the instrument panel J/B.
CHECK:
Measure the resistance.
OK:
Below 1 W
NG Replace fuse.
OK
2 Inspect lumbar support control switch.
PREPARATION:
Disconnect the lumbar support control switch connector.
CHECK:
Measure the resistance of each terminal, as shown in the il-
lustration and table.
OK:
Tester ConnectionSwitch PositionSpecified Condition
1 ± 2HOLD (Front)Below 1 W
3 ± 4HOLD (Front)Below 1 W
1 ± 2OFFBelow 1 W
4 ± 5OFFBelow 1 W
1 ± 3RELEASE (Rear)Below 1 W
4 ± 5RELEASE (Rear)Below 1 W
NG Replace lumbar support control switch assy
(See page BO±112).
OK
Page 1725 of 4323

I28701
Wire Harness Side:
Lumbar Support Control Switch
L4
I28702
Lumbar Support Control Motor
Clockwise
Counter-
clockwise
Driving AxisL3
± DIAGNOSTICSPOWER SEAT CONTROL SYSTEM (w/ Driving Position
Memory)DI±1523
1717 Author: Date:
2005 SEQUOIA (RM1146U)
3 Check harness and connector (Power source).
CHECK:
Measure the voltage of each terminal of the wire harness side
connectors.
OK:
Tester ConnectionConditionSpecified Condition
L4±3 ± Body groundAlways10 to 14 V
CHECK:
Measure the resistance of each terminal, as shown in the il-
lustration and table.
OK:
Tester ConnectionConditionSpecified Condition
L4±2 ± Body groundAlwaysBelow 1 W
L4±5 ± Body groundAlwaysBelow 1 W
NG Repair or replace harness or connector.
OK
4 Inspect lumbar support control motor.
PREPARATION:
Remove the lumbar support control motor (See page BO±112).
CHECK:
Check that the motor rotates smoothly when the battery is con-
nected to the lumbar support control motor connector terminals.
OK:
Measurement ConditionOperational Direction
Battery positive (+) "1
Battery negative (±) " 2Clockwise
Battery positive (+) " 2
Battery negative (±) " 1Counterclockwise
NG Replace lumbar support control motor
(See page BO±112).
OK
Page 1726 of 4323
I28701
Wire Harness Side:
Lumbar Support Control Switch
L4
I28555
Wire Harness Side:
Lumbar Support
Control MotorL3
DI±1524± DIAGNOSTICSPOWER SEAT CONTROL SYSTEM (w/ Driving Position
Memory)
1718 Author: Date:
2005 SEQUOIA (RM1146U)
5 Check harness and connector (Lumbar support control switch ± lumbar support
control motor).
CHECK:
Measure the resistance of each terminal, as shown in the il-
lustration and table.
OK:
Tester ConnectionConditionSpecified Condition
L4±1 ± L3±2AlwaysBelow 1 W
L4±4 ± L3±1AlwaysBelow 1 W
L4±1 ± Body groundAlways10 kW or higher
L4±4 ± Body groundAlways10 kW or higher
NG Repair or replace harness or connector.
OK
Proceed to next circuit inspection shown in
problem symptoms table (See page
DI±1508).
Page 1727 of 4323

I28449
Position Control
ECU & Switch
SLD± SLD+ FRV± FRV+
LFT± LFT+RCL± RCL+ 2 1
21
21
2 13 M7
M7
M7
M7
M7
M7
M7
M724 6
9 7 108
BR P14
Power Seat Motor
(Driver's Seat Front Vertical Control)
P16
Power Seat Motor
(Driver's Seat Reclining Control)P
V W B G
Y L P15
Power Seat Motor
(Driver 's Seat Rear Vertical Control)
P17
Power Seat Motor
(Driver's Seat Slide Control)
± DIAGNOSTICSPOWER SEAT CONTROL SYSTEM (w/ Driving Position
Memory)DI±1525
1719 Author: Date:
2005 SEQUOIA (RM1146U)
Power seat motor circuit
CIRCUIT DESCRIPTION
When the power seat control switch is operated, a command signal is sent to the position control ECU. The
position control ECU then controls the appropriate seat motor as needed. This memory system does not use
a seat position sensor. The seat position is detected by counting pulses that are output when the motor turns.
If there is no pulse output from the motor, the motor will stop operating. The ECU is designed so that a mal-
function of the seat memory system will not interfere with manual seat control.
When the position control ECU switch assy detects the low motor speed or abnormal activity, the system
stops the motor. When the motor continuously operates for 120 seconds or more, the system will stop the
motor until the switch is turned off.
WIRING DIAGRAM
DIDEB±01
Page 1728 of 4323
I07253
1 21 2
DI±1526± DIAGNOSTICSPOWER SEAT CONTROL SYSTEM (w/ Driving Position
Memory)
1720 Author: Date:
2005 SEQUOIA (RM1146U)
INSPECTION PROCEDURE
1 Inspect power seat motor assy.
PREPARATION:
Remove the power seat motor (See page BO±112).
CHECK:
Check that the motor rotates smoothly when the battery is con-
nected to the connector terminal.
OK:
Tester ConnectionSpecified Condition
Battery positive voltage ± 1
Battery negative voltage ± 2Counterclockwise
Battery positive voltage ± 2
Battery negative voltage ± 1Clockwise
NG Replace power seat motor (See page BO±112).
OK