2001 TOYOTA SEQUOIA Page 18

DI±1348
± DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
1542 Author: Date:
2005 SEQUOIA (RM1146U)
DTC B1795 Occupant Classification ECU Circuit
Malfunction
CIRCUIT DESCRIPTION
DTC B1795 is recorded when a malfunction is detected in the occupant classification ECU.
Troubleshoot DTC B1771 first when the DTC B1771 and B1795 are output simultaneously.
DTC No.DTC Detecting ConditionTrouble Area
B1795

Occupant classification ECU circuit malfunction

The occupant classification ECU receives a short circuit to
ground signal in the passenger side buckle switch circuit
for 2 seconds.

Occupant classification ECU malfunction

Occupant classification ECU

Front seat inner belt RH

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 B1795 is output, perform troubleshooting
for the DTC.
INSPECTION PROCEDURE
HINT:

If troubleshooting (wire harness inspection) is difficult to perform, remove the passenger seat installa-
tion bolts to see the under surface of seat cushion.

In the above case, hold the seat so that it does not fall down. Holding the seat for a long period of time
may cause a problem, such as seat rail deformation. Hold the seat only as necessary.
1 Check DTC.
CHECK:
(a) Turn the ignition switch to the ON position, and wait for at least 10 seconds.
(b) Using the hand±held tester, check the DTCs of the occupant classification ECU (see page DI±1147).
RESULT:
A: DTC B1795 is output.
B: DTC B1771 and B1795 are output.
HINT:
Codes other than DTC B1771 and B1795 may be output at this time, but they are not related to this check.
B Go to DTC B1771 (see page DI±1251).
A
DIDHG±01

± DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
DI±1349
1543 Author: Date:
2005 SEQUOIA (RM1146U)
2 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
3 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 ºZero point calibrationº (see page DI±1128).
OK:
The ºCOMPLETEDº is displayed.
NEXT
4 Perform sensitivity check.
Using the hand±held tester, perform ºSensitivity checkº (see page DI±1128).
OK:
Standard value: 27 to 33 kg (59.52 to 72.75 lb)
NEXT
END

DI±1350
± DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
1544 Author: Date:
2005 SEQUOIA (RM1146U)
DTC B1796 Sleep Operation Failure Of Occupant
Classification ECU
CIRCUIT DESCRIPTION
During sleep mode, the occupant classification ECU reads the condition of each sensor while the ignition
switch is off.
In this mode, if occupant classification ECU detects an internal malfunction, DTC B1796 is output.
DTC No.DTC Detecting ConditionTrouble Area
B1796
Occupant classification ECU malfunction
Occupant classification ECU
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 B1796 is output, perform troubleshooting
for the DTC.
INSPECTION PROCEDURE
1 Check DTC.
CHECK:
(a) Turn the ignition switch to the ON position, and wait for at least 10 seconds.
(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 B1796 is not output.
HINT:
Codes other than DTC B1796 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).
DIDHH±01

± DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
DI±1351
1545 Author: Date:
2005 SEQUOIA (RM1146U)
2 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
3 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 ºZero point calibrationº (see page DI±1128).
OK:
The ºCOMPLETEDº is displayed.
NEXT
4 Perform sensitivity check.
Using the hand±held tester, perform ºSensitivity checkº (see page DI±1128).
OK:
Standard value: 27 to 33 kg (59.52 to 72.75 lb)
NEXT
END

DI±1354
± DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
1548 Author: Date:
2005 SEQUOIA (RM1146U)
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.
CHECK:
Proceed to each step according to how to read DTC.
(1) If using the hand±held tester (read the 5±digit of DTC):
Using the hand±held tester, check the DTCs (see page DI±1147).
RESULT:
DTC B1800 is output.A
DTC B1801 is output.B
DTC B1802 is output.C
DTC B1803 is output.D
(2) If not using the hand±held tester (read the 2±digit of DTC):
Check the DTCs (see page DI±1147).
RESULT:
DTC 51 is output.E
HINT:
Codes other than DTC B1800, B1801, B1802, B1803 and DTC 51 may be output at this time, but they are
not related to this check.
B Go to step 4.
C Go to step 5.
D Go to step 6.
E Go to step 7.
A

H23795H23974
H01001H23987
D+
D±
Color: Orange
D Squib
Spiral
CableA
B C D E FAirbag
Sensor
Assembly
± DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
DI±1355
1549 Author: Date:
2005 SEQUOIA (RM1146U)
2 Check connector.
CHECK:
Check that the spiral cable connectors (on the steering wheel pad side) are not damaged.
OK:
The lock button is not disengaged, or the claw of the lock is not deformed or damaged.
NG Replace spiral cable (see page RS±21).
OK
3 Check D squib circuit (short).
PREPARATION:
Release the activation prevention mechanism built into con-
nector ºBº (see page DI±1137).
CHECK:
Measure the resistance according to the value(s) in the table
below.
OK:
Tester ConnectionConditionSpecified Condition
D+ ± D±Always1 MW or higher
NG Go to step 13.
OK
Go to step 10.

H23795H23974
H01001H23987
D+
D±
Color: Orange
D Squib
Spiral
CableA
B C D E FAirbag
Sensor
Assembly
± DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
DI±1357
1551 Author: Date:
2005 SEQUOIA (RM1146U)
6 Check D squib (short to B+).
PREPARATION:
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.
(b) Measure the voltage according to the value(s) in the table
below.
OK:
Tester ConnectionConditionSpecified Condition
D+ ± Body groundIgnition switch ONBelow 1 V
D± ± Body groundIgnition switch ONBelow 1 V
NG Go to step 19.
OK
Go to step 11.
7 Check connector.
CHECK:
Check that the spiral cable connectors (on the steering wheel pad side) are not damaged.
OK:
The lock button is not disengaged, or the claw of the lock is not deformed or damaged.
NG Replace spiral cable (see page RS±21).
OK

H23795H23974
H01001H23987
D+
D±
Color: Orange
D Squib
Spiral
CableA
B C D E FAirbag
Sensor
Assembly
DI±1358
± DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
1552 Author: Date:
2005 SEQUOIA (RM1146U)
8 Check D squib circuit.
PREPARATION:
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.
(b) Measure the voltage according to the value(s) in the table
below.
OK:
Tester ConnectionConditionSpecified Condition
D+ ± Body groundIgnition switch ONBelow 1 V
D± ± Body groundIgnition switch ONBelow 1 V
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 ConnectionConditionSpecified Condition
D+ ± D±AlwaysBelow 1 W
D+ ± Body groundAlways1 MW or higher
D± ± Body groundAlways1 MW or higher
PREPARATION:
Release the activation prevention mechanism built into the con-
nector ºBº (see page DI±1137).
CHECK:
Measure the resistance according to the value(s) in the table
below.
OK:
Tester ConnectionConditionSpecified Condition
D+ ± D±Always1 MW or higher
NG Go to step 21.
OK