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Home >> Infiniti >> 2010 >> M45 Base >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - DTCS P0171 To P0456 >> DTC P0420, P0430 Three Way Catalyst Function >> Overall Function Check
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Overall Function Check

Use this procedure to check the overall function of the three way catalyst (manifold). During this check, a 1st trip DTC might not be confirmed.

WITH GST

  1. Start engine and warm it up to normal operating temperature.
  2. Turn ignition switch OFF and wait at least 10 seconds.
  3. Start engine and keep the engine speed between 3, 500 and 4, 000 RPM for at least 1 minute under no load.
  4. Let engine idle for 1 minute.
  5. Open engine hood.
  6. Set voltmeter probe between ECM terminal 55 [HO2S2 (bank 1) signal] and ground, ECM terminal 74 [HO2S2 (bank 2) signal] and ground.
  7. Keep engine speed at 2, 500 RPM constant under no load.
  8. Check that the voltage does not vary for more than 5 seconds. If the voltage fluctuation cycle takes less than 5 seconds, go to "DIAGNOSIS PROCEDURE ".
    • 1 cycle: 0.6 - 1.0 → 0 - 0.3 → 0.6 - 1.0
    Fig 1: Checking ECM Voltage
    G04900434Courtesy of NISSAN MOTOR CO., U.S.A.