Last Modified: 04-05-2023 6.11:8.1.0 Doc ID: RM100000000VJGP
Model Year Start: 2016 Model: Sienna Prod Date Range: [12/2015 -           ]
Title: DOOR LOCK: KEY REMINDER WARNING SYSTEM: Key Reminder Buzzer does not Sound; 2016 - 2020 MY Sienna [12/2015 -        ]

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 positions. The key reminder warning buzzer is activated when the main body ECU sends a key switch signal and driver side courtesy light switch signal to the combination meter.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

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 functions in accordance with How to Proceed with Troubleshooting. Then conduct the following troubleshooting procedure.

PROCEDURE

1.

CHECK FRONT DOOR COURTESY LIGHT SWITCH LH

(a) Open the driver door and check that the open door indicator on the combination meter comes on.

OK:

Open door indicator comes on.

NG

GO TO DOOR COURTESY LIGHT SWITCH CIRCUIT

OK

2.

READ VALUE USING TECHSTREAM (KEY UNLOCK WARNING SW)

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(c) Turn the Techstream on.

(d) Enter the following menus: Body Electrical / Main Body / Data List/

(e) Read the Data List according to the display on the Techstream.

Main Body

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

-

OK:

When the unlock warning switch is operated, the display changes as shown in the table.

NG

GO TO STEP 4

OK

3.

CHECK COMBINATION METER ASSEMBLY (BUZZER OPERATION)

(a) Remove the key from the key cylinder, turn the light control switch on the headlight dimmer switch assembly to the tail position, and open the driver door.

OK:

The light reminder warning buzzer sounds.

HINT:

The key reminder warning system sounds the buzzer built in to the combination meter for key reminder warnings. This buzzer is also used for the light reminder warning system. Therefore, check the operation of the combination meter buzzer by checking if the buzzer sounds to inform that the lights are still on.

OK

REPLACE MAIN BODY ECU

NG

REPLACE COMBINATION METER ASSEMBLY

4.

INSPECT UNLOCK WARNING SWITCH ASSEMBLY

(a) Remove the unlock warning switch assembly (See page 2016 - 2020 MY Sienna [12/2015 -        ]; DOOR LOCK: UNLOCK WARNING SWITCH: REMOVAL ).

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

Standard Resistance:

Tester Connection

Switch Condition

Specified Condition

1 - 2

Switch free

10 kΩ or higher

1 - 2

Switch pushed

Below 1 Ω

Text in Illustration

*a

Component without harness connected

(Unlock Warning Switch)

NG

REPLACE UNLOCK WARNING SWITCH ASSEMBLY

OK

5.

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

(a) Disconnect the D26 unlock warning switch connector.

(b) Disconnect the D13 main body ECU connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

D26-1 - D13-17 (KSW)

Always

Below 1 Ω

D26-1 - Body ground

Always

10 kΩ or higher

D26-2 - Body ground

Always

Below 1 Ω

NG

REPLACE HARNESS OR CONNECTOR

OK

6.

REPLACE MAIN BODY ECU

(a) Temporarily replace the main body ECU with a new or normally functioning one (See page 2016 - 2020 MY Sienna [12/2015 -        ]; POWER DISTRIBUTION: MAIN BODY ECU: REMOVAL ).

NEXT

7.

READ VALUE USING TECHSTREAM (KEY UNLOCK WARNING SW)

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(c) Turn the Techstream on.

(d) Enter the following menus: Body Electrical / Main Body / Data List/

(e) Read the Data List according to the display on the Techstream.

Main Body

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

-

OK:

When the unlock warning switch is operated, the display changes as shown in the table.

OK

END (MAIN BODY ECU IS DEFECTIVE)

NG

REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY