Toyota Sequoia (2005). Manual — part 527

DIDF8–01

C00083

DLC3

–

DIAGNOSTICS

MULTIPLEX COMMUNICATION SYSTEM

DI–1903

2097

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 Description

Condition

Specified Condition

SIL(7) – SG(5)

Bus ”+” line

During communication

Pulse generation

SG(5) – Body ground

Signal ground

Always

Below 1

Ω

BAT(16) – Body ground

Battery positive

Always

11 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

D05981

DLC3

Hand–held
Tester

DI–1904

–

DIAGNOSTICS

MULTIPLEX COMMUNICATION SYSTEM

2098

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

–

DIAGNOSTICS

MULTIPLEX COMMUNICATION SYSTEM

DI–1905

2099

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 Item

Trouble 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

–

DIAGNOSTICS

MULTIPLEX COMMUNICATION SYSTEM

2100

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.