Toyota Tundra. Manual — part 347

Techstream

Main Body

TECHSTREAM DATA LIST - MAIN BODY

KEY REMINDER BUZZER DOES NOT SOUND

DESCRIPTION

The key reminder warning buzzer sounds when the driver side door is opened while the ignition switch is in the
LOCK or ACC position. The key reminder warning buzzer is activated when the main body ECU sends a key
switch signal and driver side courtesy switch signal to the combination meter.

HINT:

Since the key reminder warning system has functions that use CAN communication, first confirm that there is
no malfunction in the communication system by inspecting the CAN communication function in accordance
with the "HOW TO PROCEED WITH TROUBLESHOOTING" procedures. Then, conduct the following
inspection procedure.

WIRING DIAGRAM

Fig. 71: Key Reminder Warning Buzzer - Wiring Diagram

Tester Display

Measurement Item/Range

Normal Condition

Diagnostic

Note

Key Unlock

Warning SW

Unlock warning switch signal /
ON or OFF

ON: Key is in ignition key
cylinder
OFF: No key is in ignition
key cylinder

-

D Door

Courtesy SW

Front door courtesy light switch
LH signal / ON or OFF

ON: Front door courtesy
light switch LH ON
OFF: Front door courtesy
light switch LH OFF

-

2009 Toyota Tundra

2009 ACCESSORIES AND EQUIPMENT Door Lock - Tundra

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

INSPECTION PROCEDURE

1. READ VALUE OF TECHSTREAM (FRONT DOOR COURTESY SWITCH LH)

a. Check the Data List for proper functioning of the front door courtesy light switch LH.

Techstream

Main Body

TECHSTREAM DATA LIST - MAIN BODY

OK: ON (driver door is open) appears on the screen.

NG: Go TO LIGHTING SYSTEM (See DOOR COURTESY SWITCH CIRCUIT )

OK: Go to next step

2. READ VALUE OF TECHSTREAM (UNLOCK WARNING SWITCH)

a. Check the Data List for proper functioning of the unlock warning switch.

Techstream

Main Body

TECHSTREAM DATA LIST - MAIN BODY

OK: ON (Key is in ignition key cylinder) appears on the screen.

NG: Go to step 3

OK: REPLACE MAIN BODY ECU

3. INSPECT UNLOCK WARNING SWITCH ASSEMBLY

Tester Display

Measurement Item/Range

Normal Condition

Diagnostic

Note

D Door

Courtesy SW

Front door courtesy light switch LH
signal / ON or OFF

ON: Driver side door
is open
OFF: Driver side door
is closed

-

Tester Display

Measurement Item/Range

Normal Condition

Diagnostic

Note

Key Unlock

Warning SW

Unlock warning switch
signal /ON or OFF

ON: Key is in ignition key
cylinder
OFF: No key is in ignition
key cylinder

-

2009 Toyota Tundra

2009 ACCESSORIES AND EQUIPMENT Door Lock - Tundra

a. Remove the unlock warning switch (see REMOVAL ).

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

Standard resistance

UNLOCK WARNING SWITCH ASSEMBLY STANDARD RESISTANCE
SPECIFICATION

Fig. 72: Identifying Unlock Warning Switch Assembly
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

NG: REPLACE UNLOCK WARNING SWITCH ASSEMBLY (see REMOVAL )

OK: Go to next step

4. CHECK HARNESS AND CONNECTOR (UNLOCK WARNING SWITCH - MAIN BODY ECU

AND BODY GROUND)

a. Disconnect the J18 switch connector.

b. Disconnect the J1 ECU connector.

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

Standard resistance

Tester Connection Switch Condition Specified Condition

1 - 2

Not pushed

10 kohms or higher

Pushed

Below 1 ohms

2009 Toyota Tundra

2009 ACCESSORIES AND EQUIPMENT Door Lock - Tundra

HARNESS AND CONNECTOR (UNLOCK WARNING SWITCH - MAIN BODY ECU
AND BODY GROUND) STANDARD RESISTANCE SPECIFICATION

Fig. 73: Identifying J18 Switch And J1 ECU Connector
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: Go to next step

5. CHECK COMBINATION METER ASSEMBLY (OPERATION)

a. Temporarily replace the combination meter assembly with a new or normally functioning one (see

REMOVAL ).

b. Check the key reminder warning system function.

OK: The key reminder warning system functions properly.

Tester Connection

Condition Specified Condition

J18-1-J1 - 5 (KSW)

Always

Below 1 ohms

J18-2 - Body ground

Always

10 kohms or higher

J1-5 (KSW) - Body ground Always

10 kohms or higher

2009 Toyota Tundra

2009 ACCESSORIES AND EQUIPMENT Door Lock - Tundra