Toyota Venza manuals

Toyota Venza: Security Horn Circuit

DESCRIPTION

When the theft deterrent system is switched from the armed state to the alarm sounding state, the main body ECU (driver side junction block assembly) controls the security horn.

WIRING DIAGRAM


PROCEDURE

1.

PERFORM ACTIVE TEST USING TECHSTREAM

(a) Connect the Techstream to the DLC3.

(b) Turn the engine switch on (IG).

(c) Turn the Techstream on.

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

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

2.

INSPECT SECURITY HORN ASSEMBLY

(a) Remove the security horn assembly (See page ).



(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

3.

INSPECT SEC HORN RELAY

(a) Remove the SEC HORN relay from the engine room relay block.


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

Standard Resistance:

Tester Connection

Condition

Specified Condition

3 - 5

Battery voltage applied to terminals 1 and 2

Below 1 Ω

3 - 5

Battery voltage not applied between terminals 1 and 2

10 kΩ or higher


NG

REPLACE SEC HORN RELAY


OK

4.

CHECK HARNESS AND CONNECTOR (SEC HORN RELAY POWER SOURCE)

(a) Measure the voltage according to the value(s) in the table below.

Standard Voltage:

Tester Connection

Condition

Specified Condition

Engine room relay block SEC HORN relay terminal 1 - Body ground

Always

Below 1 V

Text in Illustration

*1

Engine Room Relay Block

*2

SEC HORN Relay Terminal



NG

REPAIR OR REPLACE HARNESS OR CONNECTOR


OK

5.

CHECK HARNESS AND CONNECTOR (SEC HORN RELAY - MAIN BODY ECU)

(a) Disconnect the D51 main body ECU (driver side junction block assembly) connector.


(b) Measure the resistance on the relay block side according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

Engine room relay block SEC HORN relay terminal 1 - D51-6 (SH)

Always

Below 1 Ω

Engine room relay block SEC HORN relay terminal 1 - Body ground

Always

10 kΩ or higher

Text in Illustration

*1

Engine Room Relay Block

*2

SEC HORN Relay Terminal

*3

Front view of wire harness connector

(to Main Body ECU (Driver Side Junction Block Assembly))


NG

REPAIR OR REPLACE HARNESS OR CONNECTOR


OK

6.

CHECK HARNESS AND CONNECTOR (SEC HORN RELAY POWER SOURCE)

(a) Measure the voltage according to the value(s) in the table below.

Standard Voltage:

Tester Connection

Condition

Specified Condition

Engine room relay block SEC HORN relay terminal 3 - Body ground

Always

Below 1 V

Text in Illustration

*1

Engine Room Relay Block

*2

SEC HORN Relay Terminal



NG

REPAIR OR REPLACE HARNESS OR CONNECTOR


OK

7.

CHECK HARNESS AND CONNECTOR (SEC HORN RELAY - SECURITY HORN ASSEMBLY)

(a) Disconnect the A23 security horn assembly connector.


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

Standard Resistance:

Tester Connection

Condition

Specified Condition

Engine room relay block SEC HORN relay terminal 5 - A23-1

Always

Below 1 Ω

Engine room relay block SEC HORN relay terminal 5 - Body ground

Always

10 kΩ or higher

Text in Illustration

*1

Engine Room Relay Block

*2

SEC HORN Relay Terminal

*3

Front view of wire harness connector

(to Security Horn Assembly)


OK

REPLACE MAIN BODY ECU (DRIVER SIDE JUNCTION BLOCK ASSEMBLY)


NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

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