Toyota Tundra. Manual — part 2564

If trouble is detected during the primary check, the SRS warning light remains on even after
the primary check period (approximately 6 seconds) has elapsed.

b. Constant check.

1. After the primary check, the center airbag sensor constantly monitors the airbag system for

trouble.

HINT:

If trouble is detected during the constant check, the center airbag sensor functions as follows:



The SRS warning light comes on.



The SRS warning light goes off, and then comes on. This blinking pattern indicates a
source voltage drop. The SRS warning light goes off 10 seconds after the source
voltage returns to normal.

c. Review.

1. When the airbag system is normal:

The SRS warning light comes on only during the primary check period (for approximately 6
seconds) after the ignition switch is turned ON.

2. When the airbag system has trouble:



The SRS warning light remains on even after the primary check period has elapsed.



The SRS warning light goes off after the primary check, but comes on again during the
constant check.



The SRS warning light does not come on when turning the ignition switch from OFF
to ON.

HINT:

The center airbag sensor functions to keep the SRS warning light on if the airbag has been
deployed.

3. CHECK SRS WARNING LIGHT

a. Turn the ignition switch ON, and check that the SRS warning light comes on for approximately 6

seconds (primary check).

b. Check that the SRS warning light goes off approximately 6 seconds after the ignition switch is

turned ON (constant check).

HINT:

When any of the following symptoms occur, refer to PROBLEM SYMPTOMS TABLE .



The SRS warning light comes on occasionally after the primary check period has elapsed.



The SRS warning light comes on, but a DTC is not output.

2009 Toyota Tundra

2009 RESTRAINTS Supplemental Restraint System - Tundra



The ignition switch is turned from OFF to ON, but the SRS warning light does not come on.

Fig. 42: Identifying SRS Warning Light
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

4. FUNCTION OF PASSENGER AIRBAG ON/OFF INDICATOR

a. Initial check

1. Turn the ignition switch ON.

2. for Regular Cab:

Turn the passenger airbag cut-off switch ON.

3. The passenger airbag ON/OFF indicator comes on for approximately 4 seconds, then goes off

for approximately 2 seconds.

4. Approximately 6 seconds after the ignition switch is turned ON, the passenger airbag

ON/OFF indicator will be ON or OFF depending on the conditions listed below.

INDICATOR CONDITION TABLE

HINT:



The passenger airbag ON/OFF indicator is based on the timing table below in order to
check the indicator light circuit.



When the occupant classification system has trouble, both the SRS warning light and
the passenger airbag ON/OFF indicator ("OFF") come on. In this case, check the DTCs
in "AIRBAG SYSTEM" first. Then troubleshoot the occupant classification system if
DTC B1650/32 is detected, and troubleshoot the passenger airbag ON/OFF indicator if
DTC B1660/43 is detected.

Condition

"ON" indicator "OFF" Indicator

Vacant

OFF

OFF

Adult is seated

ON

OFF

Child is seated

OFF

ON

Child restraint system is set

OFF

ON

Front passenger occupant classification failure

OFF

ON

2009 Toyota Tundra

2009 RESTRAINTS Supplemental Restraint System - Tundra

Fig. 43: Identifying Passenger Airbag ON/OFF Indicator Flash-Pattern
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

5. CHECK PASSENGER AIRBAG ON/OFF INDICATOR

a. Turn the ignition switch ON.

b. for Regular Cab:

Turn the passenger airbag cut-off switch ON.

c. Check that the passenger airbag ON/OFF indicator ("ON" and "OFF") comes on for approximately

4 seconds, then goes off for approximately 2 seconds.

HINT:

Refer to the table in the previous step regarding the passenger airbag ON/OFF indicator when the
ignition switch is turned ON and approximately 6 seconds have passed.

Regular Cab:

When the passenger airbag cut-off switch is turned OFF, the ON/OFF indicator ("OFF") always
comes on.

Fig. 44: Identifying Passenger Airbag ON/OFF Indicator

2009 Toyota Tundra

2009 RESTRAINTS Supplemental Restraint System - Tundra

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

6. ACTIVATION PREVENTION MECHANISM

a. FUNCTION OF ACTIVATION PREVENTION MECHANISM

1. An activation prevention mechanism is built into the connector (on the center airbag sensor

side) of the airbag system squib circuit to prevent accidental airbag activation.

2. This mechanism closes the circuit when the connector is disconnected by bringing the short

spring into contact with the terminals and shutting off external electricity to prevent
accidental airbag activation.

b. RELEASING OF ACTIVATION PREVENTION MECHANISM

1. To release the activation prevention mechanism, insert a piece of paper with the same

thickness as the male terminal (approximately 0.5 mm (0.02 in.)) between the terminals and
the short spring to break the connection.

2. Refer to the following graphics concerning connectors utilizing the activation prevention

mechanism and its release method.

CAUTION: Never release the activation prevention mechanism on the

squib connector even when inspecting with the squib
disconnected.

NOTE:



Do not release the activation prevention mechanism unless specia

directed by the troubleshooting procedure.



To prevent the terminal and the short spring from being damaged,

use a piece of paper with the same thickness as the male terminal

2009 Toyota Tundra

2009 RESTRAINTS Supplemental Restraint System - Tundra