3. Check Ho2S1 Input Signal Circuit For Open And Short

WARNING: This page is about a different car, the 2004 Infiniti G35. However, it is still accessible from the selected car via links, so may be relevant.

Check harness continuity between ECM terminal and HO2S1 terminal as follows.
Refer to Wiring Diagram.

Fig 1: Checking HO2S1 Input Signal Circuit For Open And Short
Courtesy of NISSAN MOTOR CO., U.S.A.
1. Continuity should exist.
Check harness continuity between the following terminals and ground.
Refer to Wiring Diagram.

Fig 2: Checking HO2S1 Input Signal Circuit For Open And Short
Courtesy of NISSAN MOTOR CO., U.S.A.
1. Continuity should not exist.
Also check harness for short to power.

OK or NG

OK: GO TO 4.

NG: Repair open circuit or short to ground or short to power in harness or connectors.