How do I change my CARFIT PULS Sensor Batteries? To change your CARFIT PULS Sensor batteries simply do the following. Carefully pop the top off the CARFIT PULS. Remove the three batteries. Replace with three new CR2032 batteries. Put the top of the CARFIT PULS back on and snap it into place. Have more questions? Submit a request 0 Comments Please sign in to leave a comment.