Hi, my name is***** your mechanic automotive expert, and I will be happy to assist you today. In some cases, I may need more information to assist better. I apologize for any delay.
Dear customer, there are several factors that can influence in the problem you have due to the discharge of the battery, the most worrying of it is that the immobilizer system has been activated in the vehicle. But there are several factors that have to be checked before, starting with a check of the status of the ignition relays located under the engine compartment and under the dashboard, sometimes when the battery is discharged when recharging and connecting it can cause a sudden rise in voltage, which can damage fuses and relays.
The second thing is that it is recommended to check very well the connections of the battery and the starter motor, in addition to checking that the starter motor does not have any kind of problems.
Third, check with a new battery because a battery with old cells, although it apparently indicates that it has a good charge, may not be functional for ignition.
Finally, if the problem persists, you must proceed to deactivate the vehicle's immobilizer system through its programming. To do so, a diagnostic tool with Nissan software is needed to do the relative checkes.
My goal is to give you the best advice i can, I hope to be helpful, if you have any doubt or want to know anything else please do not hesitate to reply back.
Kind regards, Sebastian.