FixVault
Home
›
Jeep
›
2023
›
Compass Red
›
Repair and Diagnosis
›
Engine Performance
›
System
›
2.0L - DTCS P032F To P0440
›
DTC Troubleshooting
›
P0420-Catalyst System Efficiency Below Threshold Bank 1
›
Set Condition
Set Condition
The Powertrain Control Module (PCM) detects a failed catalyst if the final Downstream O2 Sensor state of change test ratio is greater than the calibrated fail threshold.