Whether a backlog affects placements in NIT Jalandhar or not varies from company to company. These are various circumstances of backlogs and their consequences:
No current backlogs: this means you had a backlog in previous years that has already been cleared. In this case, most companies allow you to sit for placements.
Current backlog: This means you have a backlog in the current semester. Most companies don’t let you sit for placements but some ask you to clear your backlog and then join.
Backlog after placement: If you get a backlog in a subject after the placement, then you will have to clear it before joining. In case you have more than one backlog and are unable to clear it, you will end up losing your job.
So it’s better you focus on your CGPA, especially in the last semester. We know that prevention is better than cure. Rather than losing your job, it’s better you work hard on your grades.