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Home >> Infiniti >> 2021 >> QX50 Essential, 4WD >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Control System (DTC/Circuit Diagnosis) (2 Of 5) >> DTC/Circuit Diagnosis >> DTC P0420: Three Way Catalyst Function >> DTC Description >> DTC Detection Logic
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DTC Detection Logic

DTC

CONSULT screen terms

(Trouble diagnosis content)

DTC detection condition

P0420

00

TW CATALYST SYS-B1

(Catalyst system efficiency below threshold bank 1)

Diagnosis condition

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Signal (terminal)

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Threshold

  • Three way catalyst (manifold) does not operate properly
  • Three way catalyst (manifold) does not have enough oxygen storage capacity

Diagnosis delay time

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