TOYOTA SEQUOIA 2001 Service Repair Manual

I18627
B11
B10
± DIAGNOSTICSMULTIPLEX COMMUNICATION SYSTEM
DI±1899
2093 Author: Date:
2005 SEQUOIA (RM1146U)
5. CHECK BACK DOOR ECU
(a) Disconnect the B10 and B11 ECU connectors.
(b) Measure the resistance or voltage of each terminal of the wire harness side connector.
Standard:
Symbols (Terminals No.)Wiring ColorTerminal DescriptionConditionSpecified Condition
MPX2 (B11±1) ± Body groundB ± Body groundMPX lineAlways10 kW or higher
MPX1 (B11±2) ± Body groundLG±R ±
Body groundMPX lineAlways10 kW or higher
GND (B11±3) ± Body groundW±B ±
Body groundGroundAlwaysBelow 1 W
BDR (B11±4) ± Body groundL±W ±
Body ground+B (BATT) power supplyAlways10 to 14 V
BECU (B11±5) ± Body groundW±R ±
Body ground+B (BATT) power supplyAlways10 to 14 V
SIG (B11±6) ± Body groundB±R ±
Body groundIgnition power supplyIgnition switch ON10 to 14 V
If the result is not as specified, there may be a malfunction on the wire harness side.

I27703
C5
C6
DI±1900
± DIAGNOSTICSMULTIPLEX COMMUNICATION SYSTEM
2094 Author: Date:
2005 SEQUOIA (RM1146U)
6. CHECK COMBINATION METER
(a) Disconnect the C5 and C6 meter connectors.
(b) Measure the resistance or voltage of each terminal of the wire harness side connector.
Standard:
Terminals No.Wiring ColorTerminal DescriptionConditionSpecified Condition
C6±24 ± Body groundB±O ±
Body groundIgnition power supplyIgnition switch ON10 to 14 V
C6±23 ± Body groundW±R ±
Body ground+B (BATT) power supplyAlways10 to 14 V
C5±30 ± Body groundW ± Body groundMPX lineAlways10 kW or higher
C5±31 ± Body groundLG±R ±
Body groundMPX lineAlways10 kW or higher
C5±32 ± Body groundLG±B ±
Body groundMPX lineAlways10 kW or higher
C6±12 ± Body groundBR ±
Body groundGroundAlwaysBelow 1 W
C5±28 ± Body groundB±R ±
Body groundIgnition power supplyIgnition switch ON10 to 14 V
If the result is not as specified, there may be a malfunction on the wire harness side.

I27716
M7
M6
± DIAGNOSTICSMULTIPLEX COMMUNICATION SYSTEM
DI±1901
2095 Author: Date:
2005 SEQUOIA (RM1146U)
7. CHECK MEMORY SEAT ECU & SWITCH (w/ Driving Position Memory)
(a) Disconnect the M6 and M7 ECU connectors.
(b) Measure the resistance or voltage of each terminal of the wire harness side connector.
Standard:
Symbols (Terminals No.)Wiring ColorTerminal DescriptionConditionSpecified Condition
MPX1 (M6±1) ± Body groundW ± Body groundMPX lineAlways10 kW or higher
IG (M6±4) ± Body groundB±R ±
Body groundIgnition power supplyIgnition switch ON10 to 14 V
SYSB (M6±8) ± Body groundW±R ±
Body ground+B (BATT) power supplyAlways10 to 14 V
GND (M7±1) ± Body groundW±B ±
Body groundGroundAlwaysBelow 1 W
+B (M7±5) ± Body groundL±O ±
Body ground+B (BATT) power supplyAlways10 to 14 V
If the result is not as specified, there may be a malfunction on the wire harness side.

I15876
I19I20I21I22
DI±1902
± DIAGNOSTICSMULTIPLEX COMMUNICATION SYSTEM
2096 Author: Date:
2005 SEQUOIA (RM1146U)
8. CHECK A/C ECU (INTEGRATION CONTROL AND PANEL)
(a) Disconnect the I19 ECU connector.
(b) Measure the resistance or voltage of each terminal of the wire harness side connector.
Standard:
Symbols (Terminals No.)Wiring ColorTerminal DescriptionConditionSpecified Condition
+B (I19±1) ± Body groundR ± Body ground+B (BATT) power supplyAlways10 to 14 V
IG+ (I19±2) ± Body groundR±L ±
Body groundIgnition power supplyIgnition switch ON10 to 14 V
ACC (I19±11) ± Body groundP ± Body groundACC power supplyIgnition switch ACC10 to 14 V
MPX+ (I19±3) ± Body groundL±Y ±
Body groundMPX lineAlways10 kW or higher
MPX± (I19±13) ± Body groundLG±B ±
Body groundMPX lineAlways10 kW or higher
GND (I19±10) ± Body groundO ± Body groundGroundAlwaysBelow 1 W
If the result is not as specified, there may be a malfunction on the wire harness side.

DIDF8±01
C00083DLC3
± DIAGNOSTICSMULTIPLEX COMMUNICATION SYSTEM
DI±1903
2097 Author: Date:
2005 SEQUOIA (RM1146U)
DIAGNOSIS SYSTEM
1. DIAGNOSIS SYSTEM
(a) Inspect the battery voltage.
Battery voltage: 11 to 14 V
If voltage is below 11 V, recharge the battery before proceeding.
(b) Check the DLC3.
The body ECU uses ISO 9141±2 for communication. The
terminal arrangement of the DLC3 complies with SAE
J1962 and matches the ISO 9141±2 format.
Verify the conditions listed in the table below:
Symbols (Terminals No.)Terminal DescriptionConditionSpecified Condition
SIL(7) ± SG(5)Bus º+º lineDuring communicationPulse generation
SG(5) ± Body groundSignal groundAlwaysBelow 1 W
BAT(16) ± Body groundBattery positiveAlways11 to 14 V
HINT:
If the hand±held tester display shows UNABLE TO CONNECT
TO VEHICLE when the cable of the hand±held tester is con-
nected to the DLC3, the ignition switch is turned to the ON posi-
tion and the tester is operated, there is a problem on either the
vehicle side or the tester side.

If communication is normal when the tester is connected
to another vehicle, inspect the DLC3 on the original ve-
hicle.

If communication is still not possible when the tool is con-
nected to another vehicle, the problem is probably in the
tester itself, so consult the Service Department listed in
the tester's instruction manual.

DIDF9±01
D05981DLC3
Hand±held
Tester
DI±1904
± DIAGNOSTICSMULTIPLEX COMMUNICATION SYSTEM
2098 Author: Date:
2005 SEQUOIA (RM1146U)
DTC CHECK / CLEAR
1. DTC CHECK
(a) Checking DTCs using the hand±held tester.
(1) Connect the hand±held tester to the DLC3.
(2) Turn the ignition switch ON.
(3) Read DTCs by following the prompts on the tester
screen.
HINT:
Refer to the hand±held tester operator's manual for further de-
tails.
2. DTC CLEARANCE
A multiplex DTC indicates that a problem has been detected in
the multiplex communication system. Once the problem is
solved and the system begins to operate as designed, the DTC
will be cleared automatically. There is no need to manually clear
a multiplex DTC using the hand±held tester.

DI3IR±10
± DIAGNOSTICSMULTIPLEX COMMUNICATION SYSTEM
DI±1905
2099 Author: Date:
2005 SEQUOIA (RM1146U)
DIAGNOSTIC TROUBLE CODE CHART
If a trouble code is indicated during the DTC check, check the components listed for that code in the table
below (proceed to the page given for that code).
DTC No.
(See Page)Detection ItemTrouble Area
B1211
(DI±1908)Driver door ECU communication stop

Driver door ECU

Wire harness

Body ECU
B1212
(DI±1911)Front passenger door ECU communication stop

Passenger door ECU

Wire harness

Body ECU
B1214
B1215
(DI±1914)Communication bus malfunction (Short to B+)
Communication bus malfunction (Short to ground)

Driver door ECU

Passenger door ECU

Back door ECU

A/C ECU (Integration control panel)

Combination meter

Memory seat ECU & switch

Wire harness

Body ECU
B1221
(DI±1924)Power window switch circuit on driver door

Power window master switch (Built in driver door ECU)

Wire harness

Body ECU
B1222
(DI±1925)Door lock switch circuit on driver door

Door lock control switch front LH (Built in driver door ECU)

Door unlock detection switch front LH

Wire harness

Body ECU
B1223
(DI±1926)Power window switch circuit on passenger door

Power window switch (Built in passenger door ECU)

Wire harness

Body ECU
B1224
(DI±1927)Door lock switch circuit on passenger door

Door lock control switch front RH (Built in passenger door
ECU)

Door unlock detection switch front RH

Wire harness

Body ECU
B1231
(DI±1928)Jam protection limit switch circuit on driver door

Limit switch (Built in power window motor)

Driver door ECU

Wire harness

Body ECU
B1232
(DI±1929)Jam protection pulse switch circuit on driver door

Pulse switch (Built in power window motor)

Driver door ECU

Wire harness

Body ECU
B1233
(DI±1930)Jam protection limit switch circuit on passenger door

Limit switch (Built in power window motor)

Passenger door ECU

Wire harness

Body ECU
B1234
(DI±1931)Jam protection pulse switch circuit on passenger door

Pulse switch (Built in power window motor)

Passenger door ECU

Wire harness

Body ECU
B1241
(DI±1932)Body ECU switch circuit diagnosis

Back door power window switch

Rear wiper and washer switch

Wire harness

Body ECU

DI±1906
± DIAGNOSTICSMULTIPLEX COMMUNICATION SYSTEM
2100 Author: Date:
2005 SEQUOIA (RM1146U)B1242
(DI±1933)
Wireless door lock tuner circuit malfunction

Wireless door lock control receiver

Wire harness

Body ECU
B1243
(DI±1935)GSW terminal circuit malfunction

Airbag sensor assembly

Wire harness

Body ECU
B1244
(DI±1937)Light sensor circuit malfunction

Automatic light control sensor

Wire harness

Body ECU
B1262
(DI±1940)A/C ECU communication stop

A/C ECU (Integration control and panel)

Wire harness

Body ECU
B1271
(DI±1943)Combination meter ECU communication stop

Combination meter

Wire harness

Body ECU
B1272
(DI±1946)Memory seat ECU communication stop
(w/ Driving position memory)
Memory seat ECU & switch

Wire harness

Body ECU
B1273
(DI±1949)Sliding roof ECU communication stop
(w/ Sliding roof)
Sliding roof ECU

Wire harness

Body ECU
B1287
(DI±1952)Back door ECU communication stop

Back door ECU

Wire harness

Body ECU
HINT:

When either DTC B1214 or B1215 is output, a DTC for another ECU communication stop may also
be output. In this case, perform troubleshooting for DTC B1214 or B1215 first. DTC B1214 or B1215
is output when a short to +B or short to ground occurs on a communication bus.

DTCs from B1221 to B1241 do not indicate that the corresponding switch is abnormal. They notify how
the switch is operating.
If the corresponding DTC is not indicated when operating a switch, there is a problem with the switch
contact.
If a DTC is indicated when not operating switches, the corresponding switch is stuck.

DI3IS±11
I27730
Instrument Panel J/B
Passenger Door ECU
(Power Window Switch) Combination Meter
Sliding Roof ECUDLC3 Body ECU
(Located behind
the instrument panel)
Driver Door ECU
(Power Window
Master Switch)
Back Door ECU
(Located inside the back door trim board) Automatic Light Control Sensor
Memory Seat ECU
& SwitchAirbag
Sensor
Assy
Power Window
Motor Front RH

Limit Switch

Pulse Switch Power Window
Motor Front LH

Limit Switch

Pulse Switch
A/C ECU
(Integration Control and Panel)
± DIAGNOSTICSMULTIPLEX COMMUNICATION SYSTEM
DI±1907
2101 Author: Date:
2005 SEQUOIA (RM1146U)
PARTS LOCATION

DIDFB±01
DI±1908
± DIAGNOSTICSMULTIPLEX COMMUNICATION SYSTEM
2102 Author: Date:
2005 SEQUOIA (RM1146U)
CIRCUIT INSPECTION
DTC B1211 Driver door ECU communication stop
CIRCUIT DESCRIPTION
This DTC is indicated when communication fails between the driver door ECU and body ECU.
DTC No.DTC Detecting ConditionTrouble Area
B1211No communication from driver door ECU for more than 10
Driver door ECU
Wi hB1211No communication from driver door ECU for more than 10
seconds.
Wire harness

Body ECU