Toyota Sequoia (2005). Manual - part 346

H03354

H23983

H24012

Airbag 
Sensor 
Assembly

+SL

–SL

A

B

D

E

C

F

Front Airbag 
Sensor LH

Cowl Wire

Engine Room Main Wire

IA3

–

DIAGNOSTICS

SUPPLEMENTAL RESTRAINT SYSTEM

DI–1179

1373

11

Check engine room main wire (short to ground).

PREPARATION:
Disconnect the engine room main wire connector from the cowl
wire.
CHECK:
Measure the resistance according to the value(s) in the table
below.
OK:

Tester Connection

Condition

Specified Condition

IA3–1 (+SL) – 

Body ground

Always

1 M

Ω

 or higher

IA3–2 (–SL) – 

Body ground

Always

1 M

Ω

 or higher

NG

Repair or replace engine room main wire.

OK

Repair or replace cowl wire.

H02751

Airbag Sensor Assembly

S16
Side Airbag Sensor Assembly RH

A21

22

VUPR

W

2

ESR

A21

20

B

1

VUPR

ESR

DI–1180

–

DIAGNOSTICS

SUPPLEMENTAL RESTRAINT SYSTEM

1374

DTC

B1620/21 Side Airbag Sensor Assembly (RH) 

Malfunction

CIRCUIT DESCRIPTION

The side airbag sensor assembly RH consists of the safing sensor, the diagnostic circuit, the lateral decelera-
tion sensor, etc. 
If the airbag sensor assembly receives signals from the lateral deceleration sensor, it determines whether
or not the SRS should be activated. 
DTC B1620/21 is recorded when a malfunction is detected in the side airbag sensor assembly RH circuit.

DTC No.

DTC Detection Condition

Trouble Area

B1620/21

The airbag sensor assembly receives a line short circuit

signal, an open circuit signal, a short circuit to ground sig-

nal or a short circuit to B+ signal in the side airbag sensor

assembly RH circuit for 2 seconds.

Side airbag sensor assembly RH malfunction

Airbag sensor assembly malfunction

Side airbag sensor assembly RH

Airbag sensor assembly

Floor wire

WIRING DIAGRAM

DIDGU–01

C84208

H10600 H43425

H24649

CG

TC

DTC B1620/21

DLC3

Side Airbag Sensor

Assembly RH

Airbag 

Sensor 

Assembly

–

DIAGNOSTICS

SUPPLEMENTAL RESTRAINT SYSTEM

DI–1181

1375

INSPECTION PROCEDURE

CAUTION:
Be sure to perform the following procedures before troubleshooting to avoid unexpected airbag de-
ployment.
(a)

Turn the ignition switch to the LOCK position.

(b)

Disconnect the negative (–) terminal cable from the battery, and wait for at least 90 seconds.

(c)

Disconnect the connectors from the airbag sensor assembly.

(d)

Disconnect the connectors from the steering wheel pad.

(e)

Disconnect the connectors from the front passenger airbag assembly.

(f)

w/ Side and curtain shield airbag:
Disconnect the connectors from the side airbag assembly LH and RH.

(g)

w/ Side and curtain shield airbag:
Disconnect the connectors from the curtain shield airbag assembly LH and RH.

(h)

Disconnect the connectors from the front seat outer belt LH and RH.

1

Check DTC.

PREPARATION:
(a)

Connect the connectors to the airbag sensor assembly.

(b)

Connect the negative (–) terminal cable to the battery,
and wait for at least 2 seconds.

CHECK:
(a)

Turn the ignition switch to the ON position, and wait for at
least 60 seconds.

(b)

Clear the DTCs stored in memory (see page 

DI–1147

).

(c)

Turn the ignition switch to the LOCK position.

(d)

Turn the ignition switch to the ON position, and wait for at
least 60 seconds.

(e)

Check the DTCs (see page 

DI–1147

).

OK:

DTC B1620/21 is not output.

HINT:
Codes other than DTC B1620/21 may be output at this time, but
they are not related to this check.

NG

Go to step 2.

OK

From the results of the above inspection, the malfunctioning part can now be considered normal.
To make sure of this, use the simulation method to check (see page 

DI–1137

).

H01015

C91384 G27650

H23090

Side Airbag
Sensor Assembly RH

Floor Wire

Airbag 

Sensor 

Assembly

VUPR

ESR

SST

A

B

C

D

VUPR

ESR

A21

S16

DI–1182

–

DIAGNOSTICS

SUPPLEMENTAL RESTRAINT SYSTEM

1376

2

Check connection of connectors.

PREPARATION:
(a)

Turn the ignition switch to the LOCK position.

(b)

Disconnect the negative (–) terminal cable from the battery, and wait for at least 90 seconds.

CHECK:
Check that the connectors are properly connected to the airbag sensor assembly and the side airbag sensor
assembly RH.
OK:

The connectors are connected securely.

NG

Connect connectors, then go to step 1.

OK

3

Check floor wire (open).

PREPARATION:
(a)

Disconnect the connectors from the airbag sensor as-
sembly and the side airbag sensor assembly RH.

(b)

Using SST, connect S16–2 (VUPR) and S16–1 (ESR) of
connector ”C”.
SST

09843–18040

CHECK:
Measure the resistance according to the value(s) in the table
below.
OK:

Tester Connection

Condition

Specified Condition

A21–22 (VUPR) – 

A21–20 (ESR)

Always

Below 1 

Ω

NG

Repair or replace floor wire.

OK