FixVault
Home
›
Mazda
›
2004
›
3 i, Standard
›
Repair and Diagnosis
›
Engine Performance
›
System
›
On-Board Diagnostic [Engine Control System]
›
DTC P0421: Catalyst System Efficiency Below Threshold
›
California Emission Regulation Applicable Model
California Emission Regulation Applicable Model
Fig 1: DTC P0421: Detection Condition & Possible Causes Chart
Courtesy of MAZDA MOTORS CORP.
Courtesy of MAZDA MOTORS CORP.