2006 Nissan Pathfinder — Repair Manual - Starting & Charging System (Section SC)
After connecting battery cables, ensure that they are tightly clamped to battery terminals for good contact. This also applies to batteries designated as low maintenance” and maintenance-free”. To determine if a battery has been sulfated, note its voltage and current when charging it.
As shown in the figure, less current and higher voltage are observed in the initial stage of charging F sulfated batteries. A sulfated battery may sometimes be brought back into service by means of a long, slow charge, 12 hours or more, followed by G a battery capacity test. Use the following chart to correct your hydrometer reading according to electrolyte temperature.
If battery surface charge is detected while testing, the tester will prompt you to turn on the headlights to remove the surface charge. If this occurs, clean the battery post and terminals, reconnect them and restart the test. Locate the battery type and rating stamped or written on the top case of the battery to be tested.