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Home >> Toyota >> 2003 >> Matrix Base, FWD, Standard >> Repair and Diagnosis (Single Page) >> External Pages >> Different car >> Section 16 (Engine Control System Self-Diagnostics) >> Diagnostic Tests >> DTC P0430: Catalyst System Efficiency Below Threshold (Bank No. 2) >> Diagnosis & Repair
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Diagnosis & Repair

WARNING: This page is about a different car, the 2002 Toyota Sequoia. However, it is still accessible from the selected car via links, so may be relevant.
  1. Using Toyota hand-held tester or scan tool, check for any other DTCs. If only DTC P0430 exists, go to next step. If other DTCs exist, diagnose and repair those DTCs first and then retest.
  2. Check exhaust system for leaks. If no exhaust leak exists, go to next step. If exhaust leak exists, repair exhaust system as necessary.
  3. Check heated oxygen sensor (bank No. 2 sensor No. 1). See DTC P0130: HEATED OXYGEN SENSOR CIRCUIT (BANK NO. 1 SENSOR NO. 1), OR DTC P0150: HEATED OXYGEN SENSOR CIRCUIT (BANK NO. 2 SENSOR NO. 1) . If heated oxygen sensor (bank No. 2 sensor No. 1) is okay, go to next step. If heated oxygen sensor (bank No. 2 sensor No. 1) does not operate as specified, repair or replace components as necessary.
  4. Check heated oxygen sensor (bank No. 2 sensor No. 2). See DTC P0136: HEATED OXYGEN SENSOR CIRCUIT (BANK NO. 1 SENSOR NO. 2), OR DTC P0156: HEATED OXYGEN SENSOR CIRCUIT (BANK NO. 2 SENSOR NO. 2) . If heated oxygen sensor (bank No. 2 sensor No. 2) is okay, replace catalytic converter on passenger's side exhaust pipe. If heated oxygen sensor (bank No. 2 sensor No. 2) does not operate as specified, repair or replace components as necessary.
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