Last Modified: 4-30-2014 6.6 J Doc ID: RM0000018GX000X
Model Year: 2006 Model: LX470 Prod Date Range: [05/2005 -           ]
Title: THEFT DETERRENT: THEFT DETERRENT SYSTEM: Unlock Warning Switch Circuit; 2006 MY LX470 [05/2005 -        ]

Unlock Warning Switch Circuit

DESCRIPTION

The unlock warning switch turns ON when the key is inserted in the ignition key cylinder and OFF when the key is removed. The ECU operates the key confinement prevention function while the unlock warning switch is ON.

WIRING DIAGRAM

INSPECTION PROCEDURE

HINT:

When using the intelligent tester, start from *1. When not using the intelligent tester, start from *2.

PROCEDURE

1.

READ VALUE USING INTELLIGENT TESTER (UNLOCK WARNING SWITCH ASSEMBLY) *1

(a) Check the DATA LIST for proper functioning of the unlock warning switch.

Theft warning ECU assembly:

Item

Measurement Item / Display (Range)

Normal Condition

Diagnostic Note

KEY SW

Unlock warning switch signal / ON or OFF

OFF: No key is in ignition key cylinder

ON: Key is in ignition key cylinder

-

OK:

ON (key is in ignition key cylinder) appears on screen.

OK

PROCEED TO NEXT CIRCUIT INSPECTION SHOWN ON PROBLEM SYMPTOMS TABLE

NG

2.

INSPECT UNLOCK WARNING SWITCH ASSEMBLY *2

(a) Remove the switch.

(b) Measure the resistance of the switch.

Standard resistance:

Tester Connection

Condition

Specified Condition

1 - 2

Pushed (key inserted)

Below 1 Ω

Not pushed (key removed)

10 kΩ or higher

NG

REPLACE UNLOCK WARNING SWITCH ASSEMBLY

OK

3.

CHECK WIRE HARNESS (UNLOCK WARNING SWITCH - THEFT WARNING ECU AND BODY GROUND)

(a) Disconnect the U1 switch connector.

(b) Disconnect the T6 ECU connector.

(c) Measure the resistance of the wire harness side connectors.

Standard resistance:

Tester Connection

Specified Condition

U1-2 - T6-12 (KSW)

Below 1 Ω

U1-1 - Body ground

HINT:

When there is a malfunction that the theft deterrent system cannot be set, proceed to the next circuit inspection shown on the problem symptoms table before replace the theft warning ECU assembly.

NG

REPAIR OR REPLACE HARNESS AND CONNECTOR

OK

PROCEED TO NEXT CIRCUIT INSPECTION SHOWN ON PROBLEM SYMPTOMS TABLE