Last Modified: 4-30-2014 6.6 U Doc ID: RM00000185G000X
Model Year: 2006 Model: LX470 Prod Date Range: [05/2005 -           ]
Title: ENGINE IMMOBILISER: ENGINE IMMOBILISER SYSTEM: TERMINALS OF ECU; 2006 MY LX470 [05/2005 -        ]

TERMINALS OF ECU

1. CHECK TRANSPONDER KEY ECU ASSEMBLY

(a) Disconnect the T27 ECU connector.

(b) Measure the resistance and voltage of the wire harness side connector.

Symbols (Terminal No.)

Wiring Color

Terminal Description

Condition

Specified Condition

GND (T27-14) - Body ground

W-B - Body ground

Ground

Always

Below 1 Ω

+B (T27-1) - GND (T27-14)

L-W - W-B

Power source supply

Always

10 to 14 V

IG (T27-2) - GND (T27-14)

B-R - W-B

Ignition power supply

Ignition switch ON

10 to 14 V

Ignition switch OFF

Below 1 V

KSW (T27-10) - GND (T27-14)

R-B - W-B

Unlock warning switch

No key in ignition key cylinder

10 kΩ or higher

Key inserted

Below 1 Ω

CTY (T27-4) - GND (T27-14)

R-Y - W-B

Driver side courtesy switch

Driver side door closed

10 kΩ or higher

Driver side door open

Below 1 Ω

  • If the result is not as specified, there may be a malfunction on the wire harness side.

(c) Reconnect the T27 ECU connector.

(d) Measure the voltage of the connector.

Symbols (Terminal No.)

Wiring Color

Terminal Description

Condition

Specified Condition

KSW (T27-10) - GND (T27-14)

R-B - W-B

Unlock warning switch

No key in ignition key cylinder

10 to 14 V

Key inserted

Below 1 V

VC5 (T27-8) - GND (T27-14)

Y - W-B

Power source of transponder key amplifier

No key in ignition key cylinder

Below 1 V

Key inserted

4.6 to 5.4 V

TXCT (T27-12) - GND (T27-14)

V-G - W-B

Transponder key amplifier communication signal

No key in ignition key cylinder

Below 1 V

Key inserted

Pulse generation (see waveform 1)

CODE (T27-11) - GND (T27-14)

L-B - W-B

Transponder key amplifier communication signal

No key in ignition key cylinder

Below 1 V

Key inserted

Pulse generation (see waveform 2)

EFIO (T27-6) - GND (T27-14)

W - W-B

ECM output signal

Ignition switch OFF

Below 1 V

Ignition switch ON

Pulse generation (see waveform 3)

EFII (T27-7) - GND (T27-14)

Y - W-B

ECM input signal

Ignition switch OFF

10 to 14 V

Within 3 seconds after starter operates and initial combustion occurs, or within 3seconds after ignition switch first turned on (IG) after battery disconnected and connected.

Pulse generation (see waveform 4)

IND (T27-3) - GND (T27-14)

G-R - W-B

Security indicator light signal

Engine immobiliser system is unset

Below 1 V

Engine immobiliser system is set

Pulse generation

CTY (T27-4) - GND (T27-14)

R-Y - W-B

Driver side courtesy switch

Driver side door closed

10 to 14 V

Driver side door open

Below 1 V

  • If the result is not as specified, the ECU may have a malfunction

(e) Inspect using an oscilloscope.

(1) Waveform 1 (Reference)

Item

Content

Symbols (Terminal No.)

TXCT (T27-12) - GND (T27-14)

Tool Setting

5 V/DIV., 20 msec./DIV.

Condition

Key is inserted

(2) Waveform 2 (Reference)

Item

Content

Symbols (Terminal No.)

CODE (T27-11) - GND (T27-14)

Tool Setting

5 V/DIV., 20 msec./DIV.

Condition

Key is inserted

(3) Waveform 3 (Reference)

Item

Content

Symbols (Terminal No.)

EFIO (T27-6) - GND (T27-14)

Tool Setting

10 V/DIV., 50 msec./DIV.

Condition

Ignition switch ON

(4) Waveform 4 (Reference)

Item

Content

Symbols (Terminal No.)

EFII (T27-7) - GND (T27-14)

Tool Setting

5 V/DIV., 500 ms/DIV.

Condition

Within 3 seconds after starter operates and initial combustion occurs, or within 3seconds after ignition switch first turned on (IG) after battery disconnected and connected.

2. CHECK ECM

(a) Measure the resistance and voltage of the connectors.

Symbols (Terminal No.)

Wiring Color

Terminal Description

Condition

Specified Condition

E1 (E6-1) - Body ground

BR- Body ground

Ground

Always

Below 1 Ω

BATT (E10-3) - E1 (E6-1)

B-R - BR

Battery (for measuring battery voltage and for ECM memory)

Always

10 to 14 V

+BM (E10-7) - E1 (E6-1)

Y-B - BR

Power source of ECM

Ignition switch OFF

Below 1 V

Ignition switch ON

10 to 14 V

+B (E10-1) - E1 (E6-1)

B-Y -BR

Power source of ECM

Ignition switch OFF

Below 1 V

Ignition switch ON

10 to 14 V

+B2 (E10-2) - E1 (E6-1)

B-Y - BR

Power source of ECM

Ignition switch OFF

Below 1 V

Ignition switch ON

10 to 14 V

IGSW (E10-9) - E1 (E6-1)

B-R -BR

Ignition power supply of ECM

Ignition switch OFF

Below 1 V

Ignition switch ON

10 to 14 V

IMI (E9-16) - E1 (E6-1)

W-BR

Transponder key ECU input signal

Ignition switch OFF

Below 1 V

Ignition switch ON

Pulse generation (see waveform 1)

IMO (E9-15) - E1 (E6-1)

Y-BR

Transponder key ECU output signal

Ignition switch OFF

10 to 14 V

Within 3 seconds after starter operates and initial combustion occurs, or within 3seconds after ignition switch first turned on (IG) after battery disconnected and connected.

Pulse generation (see waveform 2)

  • If the result is not as specified, the ECM may have a malfunction.

(b) Inspect using an oscilloscope.

(1) Waveform 1 (Reference)

Item

Content

Symbols (Terminal No.)

IMI (E9-16) - E1 (E6-1)

Tool Setting

10 V/DIV., 50 msec./DIV.

Condition

Ignition switch ON

(2) Waveform 1 (Reference)

Item

Content

Symbols (Terminal No.)

IMO (E9-15) - E1 (E6-1)

Tool Setting

5 V/DIV., 500 ms/DIV.

Condition

Within 3 seconds after starter operates and initial combustion occurs, or within 3seconds after ignition switch first turned on (IG) after battery disconnected and connected.