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Home >> Toyota >> 2003 >> Sequoia SR5, RWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System Self Diagnostics >> Diagnostic Tests >> DTC P0420: Catalyst System Efficiency Below Threshold (Bank 1) Or P0430: Catalyst System Efficiency Below Threshold (Bank 2) >> Possible Causes
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Possible Causes

This DTC uses two-trip detection logic. For DTC detection conditions and possible causes see Fig 1.

Fig 1: DTC Detection Conditions & Possible Causes
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