Last Modified: 04-05-2023 6.11:8.1.0 Doc ID: RM100000000VJI1
Model Year Start: 2016 Model: Sienna Prod Date Range: [12/2015 - 08/2016]
Title: THEFT DETERRENT / KEYLESS ENTRY: THEFT DETERRENT SYSTEM: Horn Circuit; 2016 MY Sienna [12/2015 - 08/2016]

Horn Circuit

DESCRIPTION

When the theft deterrent system is switched from the armed state to the alarm sounding state, the main body ECU transmits a signal to cause the horn to sound at intervals of 0.4 seconds.

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

(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 horns operate.

Main Body

Tester Display

Test Part

Control Range

Diagnostic Note

Vehicle Horn

Vehicle horns

ON / OFF

-

OK:

The vehicle horns sound and stop correctly when operated through the Techstream.

NG

REPLACE MAIN BODY ECU

OK

3.

INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY

(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) Disconnect the 2D and 2F instrument panel junction block assembly connectors.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

2I-28 (HORN) - 2F-16

Always

Below 1 Ω

2I-28 (HORN) - 2D-39

Text in Illustration

*1

Component without harness connected

(Instrument Panel Junction Block Assembly)
OK

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

NG

REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY