Toyota Sequoia (2005). Manual - part 368

–

DIAGNOSTICS

SUPPLEMENTAL RESTRAINT SYSTEM

DI–1267

1461

8

Replace occupant classification ECU.

(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)

Replace the occupant classification ECU (see page 

RS–111

).

HINT:
Perform the inspection using parts from a normal vehicle if possible.

NEXT

9

Perform zero point calibration.

(a)

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

(b)

Connect the hand–held tester to the DLC3.

(c)

Turn the ignition switch to the ON position.

(d)

Using the hand–held tester, perform ”Zero point calibration” (see page 

DI–1128

).

OK:

The ”COMPLETED” is displayed.

NG

Go to step 12.

OK

10

Perform sensitivity check.

Using the hand–held tester, perform ”Sensitivity check” (see page 

DI–1128

).

OK:

Standard value: 27 to 33 kg (59.52 to 72.75 lb)

NG

Go to step 12.

OK

DI–1268

–

DIAGNOSTICS

SUPPLEMENTAL RESTRAINT SYSTEM

1462

11

Check DTC.

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 B1780 is not output.

HINT:
Codes other than DTC B1780 may be output at this time, but they are not related to this check.

NG

Go to step 12.

OK

END

–

DIAGNOSTICS

SUPPLEMENTAL RESTRAINT SYSTEM

DI–1269

1463

12

Replace front seat assembly RH.

(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)

Replace the front seat assembly RH (see page 

BO–112

, 

BO–126

).

NEXT

13

Perform zero point calibration.

(a)

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

(b)

Connect the hand–held tester to the DLC3.

(c)

Turn the ignition switch to the ON position.

(d)

Using the hand–held tester, perform ”Zero point calibration” (see page 

DI–1128

).

OK:

The ”COMPLETED” is displayed.

NEXT

14

Perform sensitivity check.

Using the hand–held tester, perform ”Sensitivity check” (see page 

DI–1128

).

OK:

Standard value: 27 to 33 kg (59.52 to 72.75 lb)

NEXT

END

DI–1270

–

DIAGNOSTICS

SUPPLEMENTAL RESTRAINT SYSTEM

1464

DTC

B1781

Occupant Classification Sensor Front RH
Circuit Malfunction

CIRCUIT DESCRIPTION

The occupant classification sensor front RH circuit consists of the occupant classification ECU and the occu-
pant classification sensor front RH.
DTC B1781 is recorded when a malfunction is detected in the occupant classification sensor front RH circuit.

DTC No.

DTC Detecting Condition

Trouble Area

B1781

The occupant classification ECU receives a line short

circuit signal, an open circuit signal, a short circuit to

ground signal or a short circuit to B+ signal in the occu-

pant classification sensor front RH for 2 seconds.

Occupant classification sensor front RH malfunction

Occupant classification ECU malfunction

Front seat assembly RH 

(Occupant classification sensor front RH)

Occupant classification ECU

Seat wire No. 1

HINT:
When DTC B1650/32 is detected as a result of troubleshooting for the supplemental restraint system, check
the DTCs stored in the occupant classification ECU. When DTC B1781 is output, perform troubleshooting
for the DTC.

DIDH6–01