Suzuki Grand Vitara JB416 / JB420. Manual - part 422

10C-18 Immobilizer Control System: 

DTC P1622: EEPROM Error

S5JB0AA304008

Detecting Condition and Trouble Area

Troubleshooting

1) Clear DTC(s) referring to “Diagnostic Trouble Code (DTC) Clearance”.
2) Turn the ignition switch to OFF position.
3) Check if DTC P1622 is still detected referring to “Diagnostic Trouble Code (DTC) Check”. If still detected, go to the 

next step. If not, the troubleshooting is completed.

4) Replace ECM with new one referring to “Engine Control Module (ECM) Removal and Installation in Section 1C”.
5) Perform “Procedure after ECM Replacement”.

DTC P1623: Unregistered Transponder

S5JB0AA304009

Detecting Condition and Trouble Area

Troubleshooting

14 Immobilizer control module (ICM) check

1) Check immobilizer control module (ICM) referring to 

“Inspection of Immobilizer Control Module (ICM) and Its 
Circuit”.

Is immobilizer control module (ICM) normal?

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

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

Step

Action

Yes

No

Detecting Condition

Trouble Area

EEPROM in ECM is corrupted.

Internal failure (EEPROM corruption) of ECM

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”.

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

Trouble Code (DTC) Check”.

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”.

2) Check if that DTC P1623 is detected referring to 

“Diagnostic Trouble Code (DTC) Check”.

Is DTC P1623 detected?

Go to Step 4.

The troubleshooting is 
completed.

Immobilizer Control System:  10C-19

DTC P1625: Immobilizer Antenna Error

S5JB0AA304010

Detecting Condition and Trouble Area

Troubleshooting

4

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

“Inspection of Immobilizer Control Module (ICM) and Its 
Circuit”.

Is immobilizer controller assembly normal?

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

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

Step

Action

Yes

No

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”.

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

Trouble Code (DTC) Check”.

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”.

2) Check if DTC P1625 is still detected referring to 

“Diagnostic Trouble Code (DTC) Check”.

Is DTC P1625 still detected?

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

The troubleshooting is 
completed.

10C-20 Immobilizer Control System: 

DTC P1636: Immobilizer Information Registration Failure

S5JB0AA304017

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
• BCM faulty
• ABS faulty
• ECM faulty

Step

Action

Yes

No

1

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

(DTC) Clearance”.

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

Trouble Code (DTC) Check”.

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”.

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 in Section 1C”.

2) Check ECM for DTC referring to “Diagnostic Trouble 

Code (DTC) Check”.

Is DTC P1636 still detected?

Recheck CAN 
communication wire 
circuits and poor 
connection at ECM, 
ABS and BCM 
connectors.

The troubleshooting is 
completed.

Immobilizer Control System:  10C-21

DTC P1638: Immobilizer Information Mismatched

S5JB0AA304018

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
• CAN communication wire circuits faulty
• BCM faulty
• ABS faulty
• ECM faulty

Step

Action

Yes

No

1

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

(DTC) Clearance”.

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

Trouble Code (DTC) Check”.

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”.

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.

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”.

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 in Section 1C”.

2) Check ECM for DTC referring to “Diagnostic Trouble 

Code (DTC) Check”.

Is DTC P1638 still detected?

Recheck CAN 
communication wire 
circuits and poor 
connection at ECM, 
ABS and BCM 
connectors.

The troubleshooting is 
completed.