2001 TOYOTA SEQUOIA steering wheel

± DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
DI±1323
1517 Author: Date:
2005 SEQUOIA (RM1146U)
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 airbag sensor
assembly.
OK:
The connectors are connected securely.
NG Connect connectors, then go to step 1.
OK
3 Prepare for inspection.
PREPARATION:
CAUTION:
Be sure to perform the following procedures before troubleshooting to avoid unexpected airbag de-
ployment.
(a) Disconnect the connectors from the airbag sensor assembly.
(b) Disconnect the connectors from the steering wheel pad.
(c) Disconnect the connectors from the front passenger airbag assembly.
(d) w/ Side and curtain shield airbag:
Disconnect the connectors from the side airbag assembly LH and RH.
(e) w/ Side and curtain shield airbag:
Disconnect the connectors from the curtain shield airbag assembly LH and RH.
(f) Disconnect the connectors from the front seat outer belt LH and RH.
NEXT

DI±1352
± DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
1546 Author: Date:
2005 SEQUOIA (RM1146U)
DTC B1800/51 Short in D Squib Circuit
DTC B1801/51 Open in D Squib Circuit
DTC B1802/51 Short in D Squib Circuit (to Ground)
DTC B1803/51 Short in D Squib Circuit (to B+)
CIRCUIT DESCRIPTION
The D squib circuit consists of the airbag sensor assembly, the spiral cable and the steering wheel pad.
The circuit instructs the SRS to deploy when deployment conditions are met.
These DTCs are recorded when a malfunction is detected in the D squib circuit.
DTC No.DTC Detection ConditionTrouble Area
B1800/51

The airbag sensor assembly receives a line short circuit
signal 5 times in the D squib circuit during primary check.

Spiral cable malfunction

D squib malfunction

Airbag sensor assembly malfunction
Steering wheel pad (D squib)

Airbag sensor assembly

Spiral cable

Cowl wire
B1801/51

The airbag sensor assembly receives an open circuit sig-
nal in the D squib circuit for 2 seconds.

Spiral cable malfunction

D squib malfunction

Airbag sensor assembly malfunction
Steering wheel pad (D squib)

Airbag sensor assembly

Spiral cable

Cowl wire
B1802/51

The airbag sensor assembly receives a short circuit to
ground signal in the D squib circuit for 0.5 seconds.

Spiral cable malfunction

D squib malfunction

Airbag sensor assembly malfunction
Steering wheel pad (D squib)

Airbag sensor assembly

Spiral cable

Cowl wire
B1803/51

The airbag sensor assembly receive a short to B+ circuit
signal in the D squib circuit for 0.5 seconds.

Spiral cable malfunction

D squib malfunction

Airbag sensor assembly malfunction
Steering wheel pad (D squib)

Airbag sensor assembly

Spiral cable

Cowl wire
DIDHI±01

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

H01003H10600H01075H23352
D Squib
Spiral
CableAirbag
Sensor
Assembly
DTC 51
DLC3
TC CG
FEDC
± DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
DI±1359
1553 Author: Date:
2005 SEQUOIA (RM1146U)
9 Replace steering wheel pad (D squib).
PREPARATION:
(a) Replace the steering wheel pad (see page RS±21).
HINT:
Perform the inspection using parts from a normal vehicle if pos-
sible.
(b) Connect the connectors to the airbag sensor assembly.
(c) 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 51 is not output.
HINT:
Codes other than DTC 51 may be output at this time, but they
are not related to this check.
NG Replace airbag sensor assembly
(see page RS±82).
OK
END

H01003H23354
D Squib
Spiral
Cable
Airbag
Sensor
Assembly
C D
E F
DI±1362
± DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
1556 Author: Date:
2005 SEQUOIA (RM1146U)
12 Check steering wheel pad (D squib).
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.
(c) From the step 11:
Disconnect the service wire from connector ºEº.
(d) Connect the connectors to the steering wheel pad.
(e) 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 B1800, B1801, B1802 or B1803 is not output.
HINT:
Codes other than DTC B1800, B1801, B1802 and B1803 may
be output at this time, but they are not related to this check.
NG
Replace steering wheel pad
(see page RS±82).
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).
HINT:

Perform the simulation method by selecting the check mode with the hand±held tester (see page
DI±1151).

After selecting the check mode, perform the simulation method by wiggling each connector of the air-
bag system or driving the vehicle on a city or rough road (see page DI±1151).

DI±1376
± DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
1570 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:
(a) 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 B1805 is output.A
DTC B1806 is output.B
DTC B1807 is output.C
DTC B1808 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 52 is output.E
HINT:
Codes other than DTC B1805, B1806, B1807, B1808 and DTC 52 may be output at this time, but they are
not related to this check.
B Go to step 3.
C Go to step 4.
D Go to step 5.
E Go to step 6.
A