Suzuki Grand Vitara JB416 / JB420 / JB419. Manual - part 541

10C-25 Immobilizer Control System: For Petrol Engine Model

6

Replacement of BCM
1) Replace BCM with new one referring to “BCM Removal 

and Installation in Section 10B”.

2) Check ECM for DTC referring to “Diagnostic Trouble 

Code (DTC) Check: For Petrol Engine Model”.

Is DTC P1638 still detected?

Go to Step 6.

The troubleshooting is 
completed.

7

Replacement of ECM
1) Replace ECM with new one referring to “Engine Control 

Module (ECM) Removal and Installation: For Petrol 
Engine Model in Section 1C”.

2) Check ECM for DTC referring to “Diagnostic Trouble 

Code (DTC) Check: For Petrol Engine Model”.

Is DTC P1638 still detected?

Recheck CAN 
communication wire 
circuits and poor 
connection at ECM, 
ABS/ESP

® control 

module and BCM 
connectors.

The troubleshooting is 
completed.

Step

Action

Yes

No

Immobilizer Control System: For Petrol Engine Model 10C-26

Inspection of Immobilizer Control Module (ICM) 
and Its Circuit

S6JB0AA314018

Immobilizer control module (ICM) and its circuit can be 
checked at immobilizer control module (ICM) wiring 
connector by measuring voltage.

CAUTION

!

 

Immobilizer control module (ICM) cannot be 
checked by itself. It is strictly prohibited to 
connect voltmeter or ohmmeter to 
immobilizer control module (ICM) with 
connector disconnected from it.

 

Voltage Check

1) Remove immobilizer control module (ICM) (1) from 

steering lock assembly or steering lock unit referring 
to “Immobilizer Control Module (ICM) Removal and 
Installation: For Petrol Engine Model”.

2) Connect immobilizer control module (ICM) connector 

(2) to immobilizer control module (ICM).

3) Check voltage at each terminal.

NOTE
As each terminal voltage is affected by the 
battery voltage, confirm that it is 11 V or more 
when the ignition switch is turned to ON 
position.

 

3. Immobilizer control module (ICM) connector (harness side view)

1

2

3

4

G24

1

2

3

5

6

I5JB0AA30005-01

Connector Terminal

Circuit

Normal Voltage

Condition

G24

1

BLK/

WHT

Power supply

About 12.0 V

Ignition switch at ON position

0.0 V

Ignition switch at OFF position

2

BLK Ground

0.0 V

Ignition switch at ON position

0.0 V

Ignition switch at OFF position

3

GRY/

BLU

Serial communication line

See the reference 
waveform.

—

0.0 V

Ignition switch at OFF position

4

PNK/

BLU

Clock line

See the reference 
waveform.

—

0.0 V

Ignition switch at OFF position

5

BLK/

RED

Illumination ring ground

0 V

• Ignition key not inserted to the key cylinder
• Door opened

0 V 

→ 12 V

• Ignition key at OFF position
• From the time door is closed to the time 

interior light faded out completely

(As the interior light fades out, the voltage 
increases.)

0 V 

→ 12 V

• Door closed
• From the ignition switch is turned ON to the 

time interior light is completely faded out

(As the interior light fades out, the voltage 
increases.)

6 WHT

Illumination ring power 
supply

About 12.0 V

Ignition switch at ON position

About 12.0 V

Ignition switch at OFF position

10C-27 Immobilizer Control System: For Petrol Engine Model

Reference Waveform

NOTE
When ECM cannot read the transponder code at the first try, ECM tries to read the transponder code 
repeatedly up to 8 times. The second waveform is the example showing that ECM read the transponder 
code successfully at the second try.

 

[A]: The transponder code read successfully at the first try.
[B]: The transponder code read successfully at the second try.

1. Serial communication line
2. Clock line
3. First try
4. Second try

Measurement terminals

CH1: G24-3 to G24-2
CH2: G24-4 to G24-2

Oscilloscope settings

CH1: 5 V/DIV
CH2: 5 V/DIV
TIME: 20 ms

Measurement condition

Right after the ignition switch is turned ON, the waveform can be read.

I4RS0AA30007-01

Immobilizer Control System: For Petrol Engine Model 10C-28

Repair Instructions

Immobilizer Control Module (ICM) Removal and 
Installation

S6JB0AA316001

Removal

1) Disconnect negative (–) cable from battery.
2) Disable air bag system referring to “Disabling Air 

Bag System in Section 8B”.

3) Remove driver air bag (inflator) module referring to 

“Driver Air Bag (Inflator) Module Removal and 
Installation in Section 8B”.

4) Remove steering wheel referring to “Steering Wheel 

Removal and Installation in Section 6B”.

5) Remove steering column lower and upper covers.
6) Remove engine start knob (1) if equipped with 

keyless start system.

7) Disconnect connector (1) from immobilizer control 

module (ICM) (2).

8) Remove a screw (3) from immobilizer control module 

(ICM).

9) Remove immobilizer control module (ICM) from 

steering lock assembly or steering lock unit.

NOTE
The antenna part of immobilizer control 
module (ICM) is fragile. Therefore, do not add 
strong power to the part or twist the part.

 

Installation
Reverse the removal procedure.

Registration of the Ignition Key

S6JB0AA316002

To finish the registration of the ignition key, the 
transponder code memorized in the transponder built in 
the ignition key has to be registered with ECM. To 
register the transponder code with ECM, perform 
“Register Ig Key” mode of SUZUKI scan tool referring to 
“SUZUKI Tech 2 Operator’s Manual”.

NOTE

• A maximum of four transponder codes can 

be registered with ECM.

• At an early part of the registration process, 

all transponder codes of the ignition keys 
in use already registered with ECM are 
cleared. Therefore, before starting the 
registration, prepare all ignition keys in 
use in addition to the new ignition key(s) to 
be registered with ECM.

 

Procedure after ECM Replacement

S6JB0AA316003

After ECM is replaced with new one or used one, the 
transponder code in the transponder built in the ignition 
key has to be registered with ECM. To register 
transponder code in the ignition key with ECM, perform 
“Replace New ECM” mode of SUZUKI scan tool 
referring to “SUZUKI Tech 2 Operator’s Manual”.

NOTE
A maximum of four transponder codes can 
be registered with ECM.

 

1

I5JB0AA30006-01

2

3

1

I4RS0BA30007-03