Toyota Tundra. Manual — part 346

B: Go to step 6

A: Go to next step

5. OVERALL ANALYSIS AND TROUBLESHOOTING*

a. See OPERATION CHECK

b. See TERMINALS OF ECU

c. See DATA LIST / ACTIVE TEST

6. REPAIR OR REPLACE

7. CONFIRMATION TEST

NEXT: END

OPERATION CHECK

1. CHECK KEY REMINDER WARNING SYSTEM

a. Check that the key reminder warning buzzer sounds.

1. With the driver side door closed, insert the key into the ignition key cylinder and then turn

the key to the LOCK or ACC position.

2. Check that the buzzer sounds intermittently if the driver side door is opened.

b. Check that the key reminder warning buzzer stops.

1. Check that the buzzer stops sounding when any of the following operations is performed

while the buzzer is sounding:



Close the driver side door (front door courtesy switch is off).



Turn the ignition switch to the ON position.



Remove the key from the ignition key cylinder.

PROBLEM SYMPTOMS TABLE

HINT:

Use the table below to help determine the cause of the problem symptom. The potential causes of the symptoms
are listed in order of probability in the "Suspected Area" column of the table. Check each symptom by checking
the suspected areas in the order they are listed. Replace parts as necessary.

Key reminder warning system

PROBLEM SYMPTOMS TABLE

Fault is listed in problem symptoms table

B

Symptom

Suspected Area

Refer To

Unlock warning switch

KEY REMINDER BUZZER

DOES NOT SOUND

2009 Toyota Tundra

2009 ACCESSORIES AND EQUIPMENT Door Lock - Tundra

TERMINALS OF ECU

1. CHECK MAIN BODY ECU

Key reminder buzzer does not
sound

Front door courtesy light switch
LH

KEY REMINDER BUZZER

DOES NOT SOUND

Harness and connector

KEY REMINDER BUZZER

DOES NOT SOUND

Main body ECU

KEY REMINDER BUZZER

DOES NOT SOUND

Combination meter

KEY REMINDER BUZZER

DOES NOT SOUND

Can communication system

KEY REMINDER BUZZER

DOES NOT SOUND

2009 Toyota Tundra

2009 ACCESSORIES AND EQUIPMENT Door Lock - Tundra

Fig. 70: Identifying Terminals Of ECU
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

a. Disconnect the J1, J4, DA, DB and DD ECU connectors.

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

MAIN BODY ECU CONNECTOR TERMINAL REFERENCE

Terminal No.

Wiring

Terminal Description

Condition

Specified

2009 Toyota Tundra

2009 ACCESSORIES AND EQUIPMENT Door Lock - Tundra

HINT:

If the result is not as specified, the ECU may have a malfunction.

DATA LIST / ACTIVE TEST

1. READ DATA LIST

HINT:

Using the Techstream to read the Data List allows the values or states of switches, sensor, actuators and
other items to be read without removing any parts. This non-intrusive inspection can be very useful
because intermittent conditions or signals may be discovered before parts or wiring is disturbed. Reading
the Data List information early in troubleshooting is one way to save diagnostic time.

a. Connect the Techstream to the DLC3.

b. Turn the ignition switch ON.

c. Turn the tester on.

d. Enter the following menus:

Techstream - Select: Body / Main Body / Data List.

e. According to the display on tester, read the "Data List".

(Symbols)

Color

Condition

DD-62 (GND1) -

Body ground

W-B - Body

ground

Ground

Always

Below 1 ohms

DD-62 (GND2) -

Body ground

DB-13 (BECU) -

Body ground

GR - Body

ground

Power source

Always

11 to 14 V

DA-1 (ALTB) -

Body ground

B - Body

ground

J4-24 (DCTY) -

Body ground

BR - Body

ground

Front door courtesy
switch LH signal

Switch pushed (Door
closed)

Below 1 ohms

Switch Not pushed

(Door open)

10 kohms or
higher

J1-5 (KSW) - Body

ground

LG - Body

ground

Key unlock warning
switch signal

No key is in ignition
key cylinder

10 kohms or

higher

Key is in ignition key

cylinder

Below 1 ohms

NOTE:

In the table below, the values listed under "Normal Condition" are
reference values. Do not depend solely on these reference values when
deciding whether a part is faulty or not.

2009 Toyota Tundra

2009 ACCESSORIES AND EQUIPMENT Door Lock - Tundra