Checking Reservoir Cap

WARNING: This page is about a different car, the 2013 Nissan Armada. However, it is still accessible from the selected car via links, so may be relevant.

Check reservoir cap relief pressure using suitable tool and Tool.
Tool number: - (J-24460-92)

Standard: 110 kPa (1.12 kg/cm ² , 16 psi)

NOTE: Apply engine coolant to the cap seal.
Replace the cap if the metal plunger cannot be seen around the edge of the black rubber gasket.
Replace the cap if deposits of waxy residue or other foreign material are on the black rubber gasket or the metal retainer.

Fig 1: Checking Reservoir Cap Relief Pressure Using Tool
Courtesy of NISSAN NORTH AMERICA, INC.
Pull negative-pressure valve to open it and make sure that it closes completely when released.
Make sure that there is no dirt or damage on the valve seat of cap negative-pressure valve.
Replace the reservoir cap if there is any damage in the negative-pressure valve, or if the open-valve pressure is outside of the limit.

Fig 2: Pulling Negative Pressure Valve
Courtesy of NISSAN NORTH AMERICA, INC.