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Home >> Mazda >> 2004 >> MPV LX >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> On-Board Diagnostic [Engine Control System AJ] >> DTC P0421, P0431:Warm-Up Catalyst System (RH) Efficiency Below Threshold; Warm-Up Catalyst System (LH) Efficiency Below Threshold >> Notes
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DTC P0421, P0431:Warm-Up Catalyst System (RH) Efficiency Below Threshold; Warm-Up Catalyst System (LH) Efficiency Below Threshold: Notes

Fig 1: DTC P0421, P0431 Detection Condition & Possible Causes Chart
G00998079Courtesy of MAZDA MOTORS CORP.
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