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Home >> Toyota >> 2004 >> Matrix Base, FWD, Standard >> Repair and Diagnosis >> External Pages >> Different car >> Section 135 (Engine Control System Self Diagnostics - V8) >> Diagnostic Tests >> DTC P0420: Catalyst System Efficiency Below Threshold (Bank 1) Or DTC P0430: Catalyst System Efficiency Below Threshold (Bank 2) >> Diagnosis & Repair
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Diagnosis & Repair

WARNING: This page is about a different car, the 2003 Toyota Tundra. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: Using Toyota hand-held tester or scan tool, read FREEZE FRAME data. Freeze frame data records engine conditions when malfunction is detected.

Perform Confirmation Engine Racing Pattern Procedure first. See CONFIRMATION ENGINE RACING PATTERN .

For diagnosis and repair procedure, see Fig 1.

For ECM location, see Figure. For ECM connector view, see Figure. For testing of systems or components, see SYSTEM & COMPONENT TESTING - V6 & V8 article. For removal and installation of components, see REMOVAL & INSTALLATION - V6 & V8 article.

Fig 1: DTCs P0420 & P0430 Diagnostic Procedure
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