Suzuki Grand Vitara JB416 / JB420 / JB419. Manual - part 540

10C-21 Immobilizer Control System: For Petrol Engine Model

DTC P1623: Unregistered Transponder

S6JB0AA314014

Wiring Diagram
Refer to “Immobilizer Control System Wiring Circuit Diagram: For Petrol Engine Model”

Detecting Condition and Trouble Area

Troubleshooting

Detecting Condition

Trouble Area

Transponder code in the transponder built in the ignition 
key is invalid.

• Use of the unregistered ignition key
• Immobilizer control module (ICM) faulty
• ECM faulty

Step

Action

Yes

No

1

Diagnostic Trouble Code (DTC) confirmation
1) Clear DTC(s) referring to “Diagnostic Trouble Code 

(DTC) Clearance: For Petrol Engine Model”.

2) Turn the ignition switch to OFF position.
3) Check if any DTC is detected referring to “Diagnostic 

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

Is DTC P1623 still detected?

Go to Step 2.

The troubleshooting is 
completed.

2

Diagnostic Trouble Code (DTC) check

Is any DTC other than P1623 is detected in Step 1?

Perform the 
troubleshooting 
referring to the 
corresponding 
flowchart, and then go 
to Step 3.

Go to Step 3.

3

Registration of the unregistered ignition key with ECM 
and Diagnostic Trouble Code (DTC) check
1) Register the transponder code in the transponder in the 

unregistered ignition key with ECM referring to 
“Registration of the Ignition Key: For Petrol Engine 
Model”.

2) Check if that DTC P1623 is detected referring to 

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

Is DTC P1623 detected?

Go to Step 4.

The troubleshooting is 
completed.

4

Immobilizer control module (ICM) check
1) Check immobilizer control module (ICM) referring to 

“Inspection of Immobilizer Control Module (ICM) and Its 
Circuit: For Petrol Engine Model”.

Is immobilizer controller assembly normal?

Replace ECM with new 
one referring to “Engine 
Control Module (ECM) 
Removal and 
Installation: For Petrol 
Engine Model in Section 
1C”, and then perform 
“Procedure after ECM 
Replacement: For 
Petrol Engine Model”.

Replace immobilizer 
control module (ICM) 
with new one referring 
to “Immobilizer Control 
Module (ICM) Removal 
and Installation: For 
Petrol Engine Model”.

Immobilizer Control System: For Petrol Engine Model 10C-22

DTC P1625: Immobilizer Antenna Error

S6JB0AA314015

Wiring Diagram
Refer to “Immobilizer Control System Wiring Circuit Diagram: For Petrol Engine Model”

Detecting Condition and Trouble Area

Troubleshooting

Detecting Condition

Trouble Area

Immobilizer control module (ICM) is faulty.

• Immobilizer control module faulty
• ECM faulty

Step

Action

Yes

No

1

Diagnostic Trouble Code (DTC) confirmation
1) Clear DTC(s) referring to “Diagnostic Trouble Code 

(DTC) Clearance: For Petrol Engine Model”.

2) Turn the ignition switch to OFF position.
3) Check if any DTC is detected referring to “Diagnostic 

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

Is DTC P1625 still detected?

Go to Step 2.

The troubleshooting is 
completed.

2

Immobilizer control module (ICM) replacement and 
Diagnostic Trouble Code (DTC) check
1) Replace immobilizer control module (ICM) referring to 

“Immobilizer Control Module (ICM) Removal and 
Installation: For Petrol Engine Model”.

2) Check if DTC P1625 is still detected referring to 

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

Is DTC P1625 still detected?

Replace ECM with new 
one referring to “Engine 
Control Module (ECM) 
Removal and 
Installation: For Petrol 
Engine Model in Section 
1C”, and then perform 
“Procedure after ECM 
Replacement: For 
Petrol Engine Model”.

The troubleshooting is 
completed.

10C-23 Immobilizer Control System: For Petrol Engine Model

DTC P1636: Immobilizer Information Registration Failure

S6JB0AA314016

Wiring Diagram
Refer to “Immobilizer Control System Wiring Circuit Diagram: For Petrol Engine Model”

DTC Detecting Condition and Trouble Area

Troubleshooting

Detecting Condition

Trouble Area

The registration of the immobilizer control system 
information in ECM is failed.

• CAN communication wire circuits faulty
• Steering angle sensor (if equipped) faulty
• Keyless start control module (if equipped) faulty
• 4WD control module (if equipped) faulty
• TCM (if equipped) faulty
• BCM faulty
• ABS/ESP

® control module faulty

• Combination meter faulty
• ECM faulty

Step

Action

Yes

No

1

Diagnostic Trouble Code (DTC) confirmation
1) Clear DTC(s) referring to “Diagnostic Trouble Code 

(DTC) Clearance: For Petrol Engine Model”.

2) Turn the ignition switch to OFF position.
3) Check if any DTC is detected referring to “Diagnostic 

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

Is DTC P1636 still detected?

Go to Step 2.

The troubleshooting is 
completed.

2

Diagnostic Trouble Code (DTC) check in ECM

Is any DTC other than P1636 detected in Step 1?

Perform the 
troubleshooting 
referring to the 
corresponding 
flowchart.

Go to Step 3.

3

Diagnostic Trouble Code (DTC) check in BCM
1) Check BCM for DTC referring to “DTC Check in Section 

10B”.

Is any DTC detected?

Perform the 
troubleshooting 
referring to the 
corresponding flowchart 
in Section 10B.

Go to Step 4.

4

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 P1636 still detected?

Go to Step 5.

The troubleshooting is 
completed.

5

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 P1636 still detected?

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

® control 

module and BCM 
connectors.

The troubleshooting is 
completed.

Immobilizer Control System: For Petrol Engine Model 10C-24

DTC P1638: Immobilizer Information Mismatched

S6JB0AA314017

Wiring Diagram
Refer to “Immobilizer Control System Wiring Circuit Diagram: For Petrol Engine Model”

DTC Detecting Condition and Trouble Area

Troubleshooting

Detecting Condition

Trouble Area

• The immobilizer control system information in ECM and 

the one in BCM does not match.

• The registration of the immobilizer control system 

information in ECM is failed.

• Use of the wrong ECM
• Steering angle sensor (if equipped) faulty
• Keyless start control module (if equipped) faulty
• 4WD control module (if equipped)
• TCM (if equipped) faulty
• CAN communication wire circuits faulty
• BCM faulty
• Combination meter faulty
• ABS/ESP

® control module faulty

• ECM faulty

Step

Action

Yes

No

1

Diagnostic Trouble Code (DTC) confirmation
1) Clear DTC(s) referring to “Diagnostic Trouble Code 

(DTC) Clearance: For Petrol Engine Model”.

2) Turn the ignition switch to OFF position.
3) Check if any DTC is detected referring to “Diagnostic 

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

Is DTC P1638 still detected?

Go to Step 2.

The troubleshooting is 
completed.

2

Diagnostic Trouble Code (DTC) confirmation
1) Disconnect negative (–) cable from battery for more than 

5 seconds.

2) Connect negative (–) cable to battery.
3) Check if any DTC is detected referring to “Diagnostic 

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

Is DTC P1638 still detected?

Go to Step 3.

The troubleshooting is 
completed.

3

Check ECM specification
1) Check ECM part number to see if ECM is applicable to 

the vehicle in service.

Is a correct ECM used for the vehicle in service?

Go to Step 2.

Replace ECM with the 
correct one and recheck 
if DTC P1638 is still 
detected by ECM.

4

Diagnostic Trouble Code (DTC) check in ECM

Is any DTC other than P1638 detected in Step 1?

Perform the 
troubleshooting 
referring to the 
corresponding 
flowchart.

Go to Step 3.

5

Diagnostic Trouble Code (DTC) check in BCM
1) Check BCM for DTC referring to “DTC Check in Section 

10B”.

Is any DTC detected?

Perform the 
troubleshooting 
referring to the 
corresponding flowchart 
in Section 10B.

Go to Step 5.