1. Check HO2S2 Heater Power Supply Circuit

WARNING: This page is about a different car, the 2004 Nissan Maxima. However, it is still accessible from the selected car via links, so may be relevant.

Turn ignition switch OFF.
Disconnect heated oxygen sensor 2 harness connector.

Fig 1: Locating Heated Oxygen Sensor 2 Harness Connectors
Courtesy of NISSAN MOTOR CO., U.S.A.
Turn ignition switch ON.
Check voltage between HO2S2 terminal 4 and ground with CONSULT-II or tester.
1. Voltage: Battery voltage

OK or NG

OK: GO TO 3 .
NG: GO TO 2.

Fig 2: Check voltage

Courtesy of NISSAN MOTOR CO., U.S.A.