Last Modified: 04-05-2023 6.11:8.1.0 Doc ID: RM100000000VJI0
Model Year Start: 2016 Model: Sienna Prod Date Range: [12/2015 - 08/2016]
Title: THEFT DETERRENT / KEYLESS ENTRY: THEFT DETERRENT SYSTEM: Security Horn Circuit; 2016 MY Sienna [12/2015 - 08/2016]

Security Horn Circuit

DESCRIPTION

When the theft deterrent system is switched from the armed state to the alarm sounding state, the main body ECU controls the security horn assembly.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

Inspect the fuses for circuits related to this system before performing the following inspection procedure.

PROCEDURE

1.

INSPECT HORNS (HORN POWER SOURCE)

(a) Press the horn switch and check if the horns sound.

Result

Result

Proceed to

Horns sound

A

Horns do not sound

B
B

GO TO HORN SYSTEM

A

2.

PERFORM ACTIVE TEST USING TECHSTREAM

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(c) Turn the Techstream on.

(d) Select the item below in the Active Test and then check that the security horn assembly operates.

Main Body

Tester Display

Test Part

Control Range

Diagnostic Note

Security Horn

Security horn

ON/OFF

-

OK:

The security horn assembly sounds and stops correctly when operated through the Techstream.

OK

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

NG

3.

INSPECT SECURITY HORN ASSEMBLY

(a) Remove the security horn assembly (See page 2016 MY Sienna [12/2015 - 08/2016]; THEFT DETERRENT / KEYLESS ENTRY: SECURITY HORN ASSEMBLY: REMOVAL ).

(b) Check the operation of the security horn assembly.

OK:

Measurement Condition

Specified Condition

Battery positive (+) → Terminal 1

Horn sounds

Battery negative (-) → Horn body
NG

REPLACE SECURITY HORN ASSEMBLY

OK

4.

CHECK HARNESS AND CONNECTOR (SECURITY HORN - INTEGRATION RELAY)

(a) Disconnect the 1C No. 1 integration relay connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

1C-4 - A14-1

Always

Below 1 Ω

1C-4 - Body ground

Always

10 kΩ or higher
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

5.

CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - INTEGRATION RELAY)

(a) Remove the main body ECU from instrument panel junction block assembly (See page 2016 - 2020 MY Sienna [12/2015 -        ]; POWER DISTRIBUTION: MAIN BODY ECU: REMOVAL ).

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

1C-7 - 2I-17 (SH)

Always

Below 1 Ω

1C- - Body ground

Always

10 kΩ or higher

Text in Illustration

*1

Component without harness connected

(Instrument Panel Junction Block Assembly)

*2

Front view of wire harness connector

(to No. 1 Integration Relay)
NG

GO TO STEP 8

OK

6.

REPLACE NO.1 INTEGRATION RELAY

(a) Replace the No. 1 integration relay with a new or normally functioning one.

NEXT

7.

PERFORM ACTIVE TEST USING TECHSTREAM

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(c) Turn the Techstream on.

(d) Select the item below in the Active Test and then check that the security horn assembly operates.

Main Body

Tester Display

Test Part

Control Range

Diagnostic Note

Security Horn

Security horn

ON/OFF

-

OK:

The security horn assembly sounds and stops correctly when operated through the Techstream.

OK

END (NO. 1 INTEGRATION RELAY IS DEFECTIVE)
NG

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

8.

CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK - INTEGRATION RELAY)

(a) Disconnect the 2F instrument panel junction block assembly connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

2F-24 - 1C-7

Always

Below 1 Ω

2F-24 - Body ground

Always

10 kΩ or higher
OK

REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR