Toyota Sequoia (2005). Manual - part 385

H23821

SVC1

SVC2

SVC4

SVC3

O7

Occupant Classification ECU:

–

DIAGNOSTICS

SUPPLEMENTAL RESTRAINT SYSTEM

DI–1335

1529

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 occupant classification ECU and the occupant clas-
sification sensors.
OK:

The connectors are connected securely.

NG

Connect connectors, then go to step 1.

OK

3

Check seat wire No. 1 (short to B+).

PREPARATION:
(a)

Disconnect the connector from the occupant classifica-
tion ECU and the 4 occupant classification sensors.

(b)

Connect the negative (–) terminal cable to the battery.

CHECK:
(a)

Turn the ignition switch to the ON position.

(b)

Measure the voltage according to the value(s) in the table
below.

OK:

Tester Connection

Condition

Specified Condition

O7–5 (SVC3) – 

Body ground

Ignition switch ON

Below 1 V

O7–6 (SVC4) – 

Body ground

Ignition switch ON

Below 1 V

O7–11 (SVC1) – 

Body ground

Ignition switch ON

Below 1 V

O7–12 (SVC2) – 

Body ground

Ignition switch ON

Below 1 V

NG

Repair or replace seat wire No. 1.

OK

H23821

H43699

H24595

SVC1

SVC2

SVC4

SVC3

O7

Occupant Classification ECU:

O8

O9

O10

O11

SVC1

SVC2

SVC3

SVC4

Occupant Classification Sensor
Front LH:

Occupant Classification Sensor
Front RH:

Occupant Classification Sensor
Rear LH:

Occupant Classification Sensor
Rear RH:

DI–1336

–

DIAGNOSTICS

SUPPLEMENTAL RESTRAINT SYSTEM

1530

4

Check seat wire No. 1 (open).

PREPARATION:
(a)

Turn the ignition switch to the LOCK position.

(b)

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

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

Tester Connection

Condition

Specified Condition

O8–1 (SVC1) – 

O7–11 (SVC1)

Always

Below 1 

Ω

O9–1 (SVC2) – 

O7–12 (SVC2)

Always

Below 1 

Ω

O10–1 (SVC3) – 

O7–5 (SVC3)

Always

Below 1 

Ω

O11–1 (SVC4) – 

O7–6 (SVC4)

Always

Below 1 

Ω

NG

Repair or replace seat wire No. 1.

OK

H23821

SVC1

SVC2

SVC4

SVC3

O7

Occupant Classification ECU:

H23821

SVC1

SVC2

SVC4

SVC3

O7

Occupant Classification ECU:

–

DIAGNOSTICS

SUPPLEMENTAL RESTRAINT SYSTEM

DI–1337

1531

5

Check seat wire No. 1 (short).

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

Tester Connection

Condition

Specified Condition

O7–5 (SVC3) – 

O7–6 (SVC4)

Always

1 M

Ω

 or higher

O7–6 (SVC4) – 

O7–11 (SVC1)

Always

1 M

Ω

 or higher

O7–11 (SVC1) – 

O7–12 (SVC2)

Always

1 M

Ω

 or higher

O7–12 (SVC2) – 

O7–5 (SVC3)

Always

1 M

Ω

 or higher

O7–12 (SVC2) – 

O7–6 (SVC4)

Always

1 M

Ω

 or higher

O7–11 (SVC1) – 

O7–5 (SVC3)

Always

1 M

Ω

 or higher

NG

Repair or replace seat wire No. 1.

OK

6

Check seat wire No. 1 (short to ground).

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

Tester Connection

Condition

Specified Condition

O7–5 (SVC3) – 

Body ground

Always

1 M

Ω

 or higher

O7–6 (SVC4) – 

Body ground

Always

1 M

Ω

 or higher

O7–11 (SVC1) – 

Body ground

Always

1 M

Ω

 or higher

O7–12 (SVC2) – 

Body ground

Always

1 M

Ω

 or higher

NG

Repair or replace seat wire No. 1.

OK

DI–1338

–

DIAGNOSTICS

SUPPLEMENTAL RESTRAINT SYSTEM

1532

7

Check DTC.

PREPARATION:
(a)

Connect the connectors to the occupant classification ECU and the 4 occupant classification sensors.

(b)

Connect the negative (–) terminal cable to the battery.

CHECK:
(a)

Turn the ignition switch to the ON position.

(b)

Clear the DTCs stored in memory (see page 

DI–1147

).

HINT:
First clear DTCs stored in the occupant classification ECU and then in the airbag sensor assembly.
(c)

Turn the ignition switch to the LOCK position.

(d)

Turn the ignition switch to the ON position.

(e)

Using the hand–held tester, check the DTCs of the occupant classification ECU (see page 

DI–1147

).

OK:

DTC B1793 is not output.

HINT:
Codes other than DTC B1793 may be output at this time, but they are not related to this check.

NG

Go to step 8.

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

).