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Last Modified: 11-27-2007 1.6 U
Service Category: Vehicle Interior Section: Theft Deterrent/Keyless Entry
Model Year: 2008 Model: LX570 Doc ID: RM000000QY701PX
Title: THEFT DETERRENT / KEYLESS ENTRY: ENGINE IMMOBILISER SYSTEM: TERMINALS OF ECU (2008 LX570)

TERMINALS OF ECU

1. CHECK ENGINE SWITCH



(a) Disconnect the E18 switch connector.

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

Terminal No. (Symbol)

Wiring Color

Terminal Description

Condition

Specified Condition

E18-5 (GND) - Body ground

BR - Body ground

Ground

Always

Below 1 Ω

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

(c) Reconnect the E18 switch connector.

(d) Measure the resistance and voltage according to the value(s) in the table below.

Terminal No. (Symbol)

Wiring Color

Terminal Description

Condition

Specified Condition

E18-8 (AGND) - Body ground

L - Body ground

Ground

Always

Below 1 Ω

E18-14 (VC5) - E18-8 (AGND)

P - L

Power supply

Key not in cabin

Below 1 V

Engine switch pressed*

4.6 to 5.4 V

E18-10 (CODE) - E18-8 (AGND)

G - L

Demodulated signal of key code output

Key not in cabin

Below 1 V

Engine switch pressed and key held close to engine switch*

Pulse generation (see waveform 1)

E18-9 (TXCT) - E18-8 (AGND)

SB - L

Key code input signal

Key not in cabin

Below 1 V

Engine switch pressed and key held close to engine switch*

Pulse generation (see waveform 2)

HINT:

*: Remove the key battery before performing this inspection.

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


(e) Using an oscilloscope, check waveform 1.

Waveform 1 (Reference)

Item

Content

Terminal No. (Symbol)

E18-10 (CODE) - E18-8 (AGND)

Tool Setting

2 V/DIV., 20 msec./DIV.

Condition

Engine switch pressed and key held close to engine switch*

HINT:

*: Remove the key battery before performing this inspection.

(f) Using an oscilloscope, check waveform 2.

Waveform 2 (Reference)

Item

Content

Terminal No. (Symbol)

E18-9 (TXCT) - E18-8 (AGND)

Tool Setting

2 V/DIV., 20 msec./DIV.

Condition

Engine switch pressed and key held close to engine switch*

HINT:

*: Remove the key battery before performing this inspection.

2. CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)



(a) Disconnect the E29 ECU connector.

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

Terminal No. (Symbol)

Wiring Color

Terminal Description

Condition

Specified Condition

E29 -17 (E) - Body ground

W-B - Body ground

Ground

Always

Below 1 Ω

E29-1 (+B) - E29-17 (E)

B - W-B

+B power supply

Always

11 to 14 V

E29-18 (IG) - E29-17 (E)

B - W-B

Ignition power supply

Engine switch off

Below 1 V

Engine switch on (IG)

11 to 14 V

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

(c) Reconnect the E29 ECU connector.

(d) Measure the resistance and voltage according to the value(s) in the table below.

Terminal No. (Symbol)

Wiring Color

Terminal Description

Condition

Specified Condition

E29-40 (AGND) - Body ground

L - Body ground

Engine switch ground

Always

Below 1 Ω

E29-30 (VC5) - E29-40 (AGND)

P - L

Engine switch power supply

Key not in cabin

Below 1 V

Engine switch pressed*

4.6 to 5.4 V

E29-9 (CODE) - E29-40 (AGND)

G- L

Engine switch CODE input

Key not in cabin

Below 1 V

Engine switch pressed and key held close to engine switch*

Pulse generation (see waveform 1)

E29-8 (TXCT) - E29-40 (AGND)

SB - L

Engine switch TX output

Key not in cabin

Below 1 V

Engine switch pressed and key held close to engine switch*

Pulse generation (see waveform 2)

HINT:

*: Remove the key battery before performing this inspection.

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


(e) Using an oscilloscope, check waveform 1.

Waveform 1 (Reference)

Item

Content

Terminal No. (Symbol)

E29-9 (CODE) - E29-40 (AGND)

Tool Setting

2 V/DIV., 20 msec./DIV.

Condition

Engine switch pressed and key held close to engine switch*

HINT:

*: Remove the key battery before performing this inspection.

(f) Using an oscilloscope, check waveform 2.

Waveform 2 (Reference)

Item

Content

Terminal No. (Symbol)

E29-8 (TXCT) - E29-40 (AGND)

Tool Setting

2 V/DIV., 20 msec./DIV.

Condition

Engine switch pressed and key held close to engine switch*

HINT:

*: Remove the key battery before performing this inspection.

3. CHECK ID CODE BOX (IMMOBILISER CODE ECU)



(a) Disconnect the E28 box connector.

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

Terminal No. (Symbol)

Wiring Color

Terminal Description

Condition

Specified Condition

E28-8 (GND) - Body ground

W-B - Body ground

Ground

Always

Below 1 Ω

E28-1 (+B) - E28-8 (GND)

B - W-B

+B power supply

Always

11 to 14 V

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

(c) Reconnect the E28 box connector.

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

Terminal No. (Symbol)

Wiring Color

Terminal Description

Condition

Specified Condition

E28-5 (EFII) - E28-8 (GND)

W - W-B

ECM input signal

Engine switch off

Below 1 V

Engine switch on (IG)

Pulse generation (see waveform 1)

E28-6 (EFIO) - E28-8 (GND)

R - W-B

ECM output signal

Engine switch off

Below 1 V

Engine switch on (IG)

Pulse generation (see waveform 2)

If the result is not as specified, the ID code box (immobiliser code ECU) may have a malfunction.


(e) Using an oscilloscope, check waveform 1.

Waveform 1 (Reference)

Item

Content

Terminal No. (Symbol)

E28-5 (EFII) - E28-8 (GND)

Tool Setting

10 V/DIV., 100 msec./DIV.

Condition

Engine switch on (IG)

(f) Using an oscilloscope, check waveform 2.

Waveform 2 (Reference)

Item

Content

Terminal No. (Symbol)

E28-6 (EFIO) - E28-8 (GND)

Tool Setting

10 V/DIV., 100 msec./DIV.

Condition

Engine switch on (IG)

4. CHECK MAIN BODY ECU (COWL SIDE JUNCTION BLOCK LH)



(a) Disconnect the 2D and 2A ECU connectors.

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

Terminal No. (Symbol)

Wiring Color

Terminal Description

Condition

Specified Condition

2D-62 (GND2) - Body ground

W-B - Body ground

Ground

Always

Below 1 Ω

2D-8 (ACC) - 2D-62 (GND2)

GR - W-B

ACC power supply

Engine switch off

Below 1 V

Engine switch on (ACC)

11 to 14 V

2A-1 (IG) - 2D-62 (GND2)

B - W-B

IG power supply

Engine switch off

Below 1 V

Engine switch on (IG)

11 to 14 V

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

5. CHECK STEERING LOCK ACTUATOR (STEERING LOCK ECU)



(a) Disconnect the E26 ECU connector.

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

Terminal No. (Symbol)

Wiring Color

Terminal Description

Condition

Specified Condition

E26-2 (SGND) - Body ground

BR - Body ground

Ground

Always

Below 1 Ω

E26-1 (GND) - Body ground

W-B - Body ground

Ground

Always

Below 1 Ω

E26-7 (B) - Body ground

R - Body ground

+B power supply

Always

11 to 14 V

E26-6 (IG2) - Body ground

B - Body ground

Ignition power supply

Engine switch off

Below 1 V

Engine switch on (IG)

11 to 14 V

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