Overall Function Check

Use this procedure to check the overall function of the heated oxygen sensor 1 circuit. During this check, a DTC might not be confirmed.

WITH GST 

1. Start engine and warm it up to normal operating temperature.
2. Set voltmeter probes between ECM terminal 50 [HO2S1 (B1) signal] or 51 [HO2S1 (B2) signal] and engine ground.
3. Check one of the following with engine speed held at 2, 000 RPM constant under no load.
   • The maximum voltage is below 0.8V at least 1 time.
   • The minimum voltage is below 0.35V at least 1 time.
4. If NG, go to "DIAGNOSTIC PROCEDURE ".
   Fig 1: Checking Voltage Between ECM Terminal 50 (B1) Or 51 (B2) And Engine Ground

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