DTC P1636: Immobilizer Information Registration Failure: Troubleshooting

WARNING: This page is about a different car, the 2007 Suzuki Grand Vitara and 2006 Suzuki Grand Vitara. However, it is still accessible from the selected car via links, so may be relevant.

TROUBLESHOOTING CHART

Step	Action	YES	NO
1	Diagnostic Trouble Code (DTC) confirmation Clear DTC(s) referring to DIAGNOSTIC TROUBLE CODE (DTC) CLEARANCE . Turn the ignition switch to OFF position. 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. Refer to appropriate DTC diagnostics.	Go to Step 3.
3	Diagnostic Trouble Code (DTC) check in BCM Check BCM for DTC referring to DTC CHECK . Is any DTC detected?	Perform the troubleshooting referring to the corresponding flowchart in Section 10B.	Go to Step 4.
4	Replacement of BCM Replace BCM with new one referring to BCM REMOVAL AND INSTALLATION . 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 Replace ECM with new one referring to ENGINE CONTROL MODULE (ECM) REMOVAL AND INSTALLATION . 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 control module and BCM connectors.	The troubleshooting is completed.