TOYOTA SEQUOIA 2001 Service Repair Manual

DIDE5±01
I27716
M7M6
± DIAGNOSTICSPOWER SEAT CONTROL SYSTEM (w/ Driving Position
Memory)DI±1509
1703 Author: Date:
2005 SEQUOIA (RM1146U)
TERMINALS OF ECU
1. CHECK POSITION CONTROL ECU & SWITCH ASSY
(a) Disconnect the M6 and M7 ECU & switch connectors.
(b) Check the voltage of each terminal of the wire harness side connectors.
Standard:
Symbols (Terminal No.)Wiring ColorTerminal DescriptionConditionSpecified Condition
GND (M7±1) ±
Body groundW±B ± Body groundGroundAlwaysBelow 1 V
+B (M7±5) ±
GND (M7±1)L±O ± W±BBatteryAlways10 to 14 V
SYSB (M6±8) ±
GND (M7±1)W±R ± W±BPower sourceAlways10 to 14 V
IG (M6±4) ± GND (M7±1)B±R ± W±BIgnition switchIgnition switch OFF " ONBelow 1 V " 10 to 14 V
MPX1 (M6±1) ±
GND (M7±1)W ± W±BCommunication signalAlways10 kW or higher
If the result is not as specified, there may be a malfunction on the wire harness side.
(c) Reconnect the M6 and M7 ECU & switch connectors.
(d) Check the voltage of each terminal of the connectors.
Standard:
Symbols (Terminal No.)Wiring ColorTerminal DescriptionConditionSpecified Condition
SLD+ (M7±2) ±
GND (M7±1)L ± W±BSliding motor signal
(Forward)Seat moving forward using
sliding switch " Others10 to 14 V " Below 1 V
SLD± (M7±3) ±
GND (M7±1)Y ± W±BSliding motor signal
(Rearward)Seat moving rearward us-
ing sliding switch " Others10 to 14 V " Below 1 V
FRV+ (M7±6) ±
GND (M7±1)G ± W±BFront vertical motor signal
(Upward)Seat cushion front portion
raising using front vertical
switch " Others
10 to 14 V " Below 1 V
FRV± (M7±4) ±
GND (M7±1)B ± W±BFront vertical motor signal
(Downward)Seat cushion front portion
lowering using front vertical
switch " Others
10 to 14 V " Below 1 V
LFT+ (M7±7) ±
GND (M7±1)W ± W±BLifter motor signal
(Upward)Seat raising using lifter
switch " Others10 to 14 V " Below 1 V
LFT± (M7±9) ±
GND (M7±1)V ± W±BLifter motor signal
(Downward)Seat lowering using lifter
switch " Others10 to 14 V " Below 1 V

DI±1510± DIAGNOSTICSPOWER SEAT CONTROL SYSTEM (w/ Driving Position
Memory)
1704 Author: Date:
2005 SEQUOIA (RM1146U) RCL+ (M7±8) ±
GND (M7±1)
P ± W±BReclining motor signal
(Forward)Seat back moving forward
using reclining switch "
Others
10 to 14 V " Below 1 V
RCL± (M7±10) ±
GND (M7±1)BR ± W±BReclining motor signal
(Rearward)Seat back moving rear-
ward using reclining switch
" Others
10 to 14 V " Below 1 V
If the result is not as specified, the position control ECU & switch assy may be malfunctioning.

DIDGG±01
± DIAGNOSTICSPOWER SEAT CONTROL SYSTEM (w/ Driving Position
Memory)DI±1511
1705 Author: Date:
2005 SEQUOIA (RM1146U)
DATA LIST / ACTIVE TEST
1. DATA LIST
HINT:
Using the DATA LIST displayed on the hand±held tester, you can read the value of the switch, sensor, etc.
without parts removal. Reading the DATA LIST as the first step of troubleshooting is one way to shorten the
labor time.
(a) Connect the hand±held tester to the DLC3.
(b) Turn the ignition switch ON.
(c) Read the DATA LIST according to the display on the tester.
D±SEAT:
ItemMeasurement Item/
Display (Range)Normal Condition
RECLIN SW REARReclining switch signal (Rearward)/
ON or OFFON: Reclining switch (Rearward) is ON
OFF: Reclining switch (Rearward) is OFF
RECLIN SW FRONTReclining switch signal (Forward)/
ON or OFFON: Reclining switch (Forward) is ON
OFF: Reclining switch (Forward) is OFF
F VTCL SW DOWNFront vertical switch signal (Downward)/
ON or OFFON: Front vertical switch (Downward) is ON
OFF: Front vertical switch (Downward) is OFF
F VTCL SW UPFront vertical switch signal (Upward)/
ON or OFFON: Front vertical switch (Upward) is ON
OFF: Front vertical switch (Upward) is OFF
LIFTER SW DOWNLifter switch signal (Downward)/
ON or OFFON: Lifter switch (Downward) is ON
OFF: Lifter switch (Downward) is OFF
LIFTER SW UPLifter switch signal (Upward)/
ON or OFFON: Lifter switch (Upward) is ON
OFF: Lifter switch (Upward) is OFF
SLIDE SW REARSliding switch signal (Rearward)/
ON or OFFON: Sliding switch (Rearward) is ON
OFF: Sliding switch (Rearward) is OFF
SLIDE SW FRONTSliding switch signal (Forward)/
ON or OFFON: Sliding switch (Forward) is ON
OFF: Sliding switch (Forward) is OFF
POWER VOLTAGEPower supply for position control ECU & switch/
MIN: 0 V, MAX: 19.89 VWithin range from 11 V to 14 V
IG SWIgnition switch status/
ON or OFFON Ignition switch is ON
OFF: Ignition switch is OFF
KEY UNLOCK SWKey unlock warning switch signal/
ON or OFFON: Key is in ignition key cylinder
OFF: Key is not in ignition key cylinder
D±DOOR WARN SWDoor courtesy switch signal/
ON or OFFON: Driver side door is open
OFF: Driver side door is closed
PNP SWPark/neutral position switch signal/
ON or OFFON: Shift lever in neutral position
OFF: Shift lever in any position except neutral
M2 SWSeat memory switch M2 signal/
ON or OFFON: Seat memory switch M2 is ON
OFF: Seat memory switch M2 is OFF
M1 SWSeat memory switch M1 signal/
ON or OFFON: Seat memory switch M1 is ON
OFF: Seat memory switch M1 is OFF
SET SWSeat memory set switch signal/
ON or OFFON: Memory set switch is ON
OFF: Memory set switch is OFF
SLIDE POSSeat sliding position/
MIN: ±4096, MAX: 4096Within range from ±4096 to 4096
RECLN POSSeatback position/
MIN: ±4096, MAX: 4096Within range from ±4096 to 4096
F VTCL POSSeat front vertical position/
MIN: ±4096 MAX: 4096Within range from ±4096 to 4096
LIFTER POSSeat lifter position/
MIN: ±4096 MAX: 4096Within range from ±4096 to 4096
MEM M1 SW
Driving position memorized with seat memory
switch M1/
MEM or NOT MEMMEM: Memorized
NOT MEM: Not memorized

DI±1512± DIAGNOSTICSPOWER SEAT CONTROL SYSTEM (w/ Driving Position
Memory)
1706 Author: Date:
2005 SEQUOIA (RM1146U)MEM M2 SW
Driving position memorized with seat memory
switch M2/
MEM or NOT MEMMEM: Memorized
NOT MEM: Not memorized
SEAT MEM M1
Seat position memorized with seat memory
switch M1/
MEM or NOT MEMMEM: Memorized
NOT MEM: Not memorized
SEAT MEM M2
Seat position memorized with seat memory
switch M2/
MEM or NOT MEMMEM: Memorized
NOT MEM: Not memorized
D±MIRR MEM1
Driver side mirror position memorized with seat
memory switch M1/
MEM or NOT MEMMEM: Memorized
NOT MEM: Not memorized
D±MIRR MEM2
Driver side mirror position memorized with seat
memory switch M2/
MEM or NOT MEMMEM: Memorized
NOT MEM: Not memorized
P±MIRR MEM M1
Passenger side mirror position memorized with
seat memory switch M1/
MEM or NOT MEMMEM: Memorized
NOT MEM: Not memorized
P±MIRR MEM M2
Passenger side mirror position memorized with
seat memory switch M2/
MEM or NOT MEMMEM: Memorized
NOT MEM: Not memorized
SLIDE MEM POS 1
Seat sliding position memorized with seat
memory switch M1/
MIN: ±4096, MAX: 4096
Within range from ±4096 to 4096
RECLIN MEM POS 1
Seat back position memorized with seat memory
switch M1/
MIN: ±4096, MAX: 4096
Within range from ±4096 to 4096
F VTCL MEM POS 1
Front vertical position memorized with seat
memory switch M1/
MIN: ±4096, MAX: 4096
Within range from ±4096 to 4096
LIFTER MEM POS 1
Lifter position memorized with seat memory
switch M1/
MIN: ±4096, MAX: 4096
Within range from ±4096 to 4096
SLIDE MEM POS 2
Seat sliding position memorized with seat
memory switch M2/
MIN: ±4096, MAX: 4096
Within range from ±4096 to 4096
RECLIN MEM POS 2
Seatback position memorized with seat memory
switch M2/
MIN: ±4096, MAX: 4096
Within range from ±4096 to 4096
F VTCL MEM POS 2
Front vertical position memorized with seat
memory switch M2/
MIN: ±4096, MAX: 4096
Within range from ±4096 to 4096
LIFTER MEM POS 2
Lifter position memorized with seat memory
switch M2/
MIN: ±4096, MAX: 4096
Within range from ±4096 to 4096
D±MIRR MEM POS 1
Driver side mirror position memorized with seat
memory switch M1/
MIN: 0, MAX: 65535
Within range from 0 to 65535
P±MIRR MEM POS 1
Passenger side mirror position memorized with
seat memory switch. M1/
MIN: 0, MAX: 65535
Within range from 0 to 65535
D±MIRR MEM POS 2
Driver side mirror position memorized with seat
memory switch M2/
MIN: 0, MAX: 65535
Within range from 0 to 65535
P±MIRR MEM POS 2
Passenger side mirror position memorized with
seat memory switch M2/
MIN: 0, MAX: 65535
Within range from 0 to 65535

± DIAGNOSTICSPOWER SEAT CONTROL SYSTEM (w/ Driving Position
Memory)DI±1513
1707 Author: Date:
2005 SEQUOIA (RM1146U)
2. ACTIVE TEST
HINT:
Performing the ACTIVE TEST using the hand±held tester allows you to operate the seat motors without parts
removal. Performing the ACTIVE TEST as the first step of troubleshooting is one way to shorten the labor
time.
(a) Connect the hand±held tester to the DLC3.
(b) Turn the ignition switch ON.
(c) Perform the ACTIVE TEST according to the display on the tester.
D±SEAT:
ItemTest DetailsDiagnostic Note
RECLINING
Test Detail:
Reclining operation FRONT/REAR/OFF
Vehicle Condition:
Vehicle is stopped
±
F VERTICAL
Test Detail:
Front vertical operation UP/DOWN/OFF
Vehicle Condition:
Vehicle is stopped
±
LIFTER
Test Detail:
Lifter operation UP/DOWN/OFF
Vehicle Condition:
Vehicle is stopped
±
SLIDE
Test Detail:
Lifter operation UP/DOWN/OFF
Vehicle Condition:
Vehicle is stopped
±

DIDE6±01
DI±1514± DIAGNOSTICSPOWER SEAT CONTROL SYSTEM (w/ Driving Position
Memory)
1708 Author: Date:
2005 SEQUOIA (RM1146U)
CIRCUIT INSPECTION
ECU power source circuit
CIRCUIT DESCRIPTION
The position control ECU is contained in the switch assy.
During manual operation, only one switch signal is accepted. If signals are input from 2 or more switches
simultaneously, all of them are ignored. However, when signals are input from only the front vertical switch
and lifter switch simultaneously, the signal from the lifter switch is accepted.
During automatic operation, a manual switch input overrides any other operations, i.e. automatic operations
stop and the manual input operation is accepted. For example, if a manual switch input is activated, during
a seat store/restore operation, the previous operation will cease and manual operation will be performed.
After the manual operation is performed, the previous automatic operation will not resume. Power mirror
store/restore operation is unaffected by manual switch inputs.
The position control ECU & switch assy disallows the restore operation of the power seat when the system
detects that the voltage of terminal SYSB is less than 8 V for 0.3 seconds or is more than 10 V for 30 seconds.
This circuit is a power source circuit of the position control ECU & switch assy.
HINT:
Manual adjustment of the slide reclining lumbar can be performed even when the ECU is not functional if
current is allowed to flow into terminals +B and SYSB.
Lumbar operation can always be performed.

I28446
B±R
W±B W±RW±L
W±B W±RW±RW±R
W±R B±R
B±R B±R
W±R L±O L±O L±O
L±O
B±Y B±R
L±O
1 2
34 5
68
5
4A
B CF
I
W
B A
A A
BB
W±B 8 11
3L CG
1C
1E 1F
1G
1J
2C 2D3A 3C
1L
1C 3A 3A
4
164
12 219
15 16 88Sub J/B No. 3J/C
J/CJ24 J/C
J/C
111Sub J/B No. 3J31 J32
J37 J38 J33 J34
J33 J34
J24 J/C Instrument Panel J/B
I18
Ignition SW
Engine Room J/B F10
FL Block
ALT
8BI2 M7
M6
M6 BI2
BI2Position Control
ECU & Switch
+B
IG
SYSB
GND 1
2
BI2
Battery
BHAM1 AM1 PWR SEATECU±IG
IG1
M7 ECU±B Short Pin
± DIAGNOSTICSPOWER SEAT CONTROL SYSTEM (w/ Driving Position
Memory)DI±1515
1709 Author: Date:
2005 SEQUOIA (RM1146U)
WIRING DIAGRAM

DI±1516± DIAGNOSTICSPOWER SEAT CONTROL SYSTEM (w/ Driving Position
Memory)
1710 Author: Date:
2005 SEQUOIA (RM1146U)
INSPECTION PROCEDURE
1 Check fuse (PWR SEAT, ECU±IG, AM1).
PREPARATION:
Remove the PWR SEAT, ECU±IG and AM1 fuses from the instrument panel J/B.
CHECK:
Measure the resistance.
OK:
Below 1 W
NG Replace fuse.
OK

I28698
Position Control ECU & Switch Assy
Wire Harness Side
Connector Front View:
M7
M6
GND
+BIG
SYSB
± DIAGNOSTICSPOWER SEAT CONTROL SYSTEM (w/ Driving Position
Memory)DI±1517
1711 Author: Date:
2005 SEQUOIA (RM1146U)
2 Inspect position control ECU & switch assy.
PREPARATION:
Disconnect the M6 and M7 ECU connectors.
CHECK:
(a) Measure the voltage of each terminal of the wire harness side connectors.
OK:
Tester Connection (Symbol)ConditionSpecified Condition
M7±5 (+B) ± Body groundAlways10 to 14 V
M6±8 (SYSB) ± Body groundAlways10 to 14 V
M6±4 (IG) ± Body groundIgnition switch OFF " ONBelow 1 V " 10 to 14 V
(b) Measure the resistance between the M7 ECU wire harness side connector and body ground.
OK:
Tester Connection (Symbol)Specified Condition
M7±1 (GND) ± Body groundBelow 1 W
NG Repair or replace harness or connector.
OK
Proceed to next circuit inspection shown in
problem symptoms table (See page
DI±1508).

I28447
D24
Seat Memory SwitchBody ECU
SET
4 3 2 1
W±BL
L±Y
G23
22 24
B6
AM1
M2 MM
B6
B6 1
2
EJ8 J/C
IE M1
M2 MRY DI±1518
± DIAGNOSTICSPOWER SEAT CONTROL SYSTEM (w/ Driving Position
Memory)
1712 Author: Date:
2005 SEQUOIA (RM1146U)
Memory switch circuit
CIRCUIT DESCRIPTION
The seat memory switch sends signals to the position control ECU & switch assy via multiplex communica-
tion to memorize a given seat position. This memory system does not use a position sensor. The seat posi-
tion 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 seat memory switch is later used to send signals to the position
control ECU to return to one of the memorized positions.
The power seat memory operation is performed only when the ignition switch is in the ON position and the
park/neutral position switch is in the P (park) position.
WIRING DIAGRAM
DIDE8±01