What Does Code P0420 Mean on a 2024 Jeep Compass?
A P0420 code on your 2024 Jeep Compass indicates the ECU has detected reduced Bank 1 catalytic converter efficiency. The redesigned 2024 Compass features a new 2.0L turbocharged inline-4 engine producing 200 horsepower and 221 lb-ft of torque, replacing the previous 2.4L Tigershark. It pairs with an 8-speed automatic transmission. On a brand-new vehicle, this code is uncommon and should be warranty-covered.
The new turbocharged engine represents a significant change from the previous naturally aspirated powerplant, and first-year calibration issues are not unusual.
Common Symptoms
- Check engine light on
- Minimal drivability changes
- Slight fuel economy decrease from the rated 27 city/32 highway MPG
- Emissions test failure
- Possible faint sulfur smell
Most Likely Causes on the 2024 Compass
1. PCM Software Calibration
The 2024 Compass features a new powertrain, and first-year models often require PCM calibration updates. A software update from Stellantis is the most likely fix for a stock vehicle.
2. Faulty O2 Sensor
A manufacturing defect in the downstream oxygen sensor can cause false P0420 readings. This is a straightforward warranty replacement.
3. Exhaust Assembly Issue
A loose exhaust connection or misaligned gasket from factory assembly can create a small leak that triggers P0420.
4. Catalytic Converter Defect
Rare on a new vehicle but possible. The turbo engine's converter is designed for higher heat loads and a factory defect would be warranty-covered.
How to Diagnose the P0420 Code
- Take the vehicle to a Jeep dealer — warranty covers all diagnosis
- Dealer checks for TSBs specific to the new 2024 Compass powertrain
- ECU software version verification and update
- O2 sensor and exhaust system inspection
- Converter efficiency testing if needed
Repair Options and Costs
Warranty Repair (Recommended)
- PCM software update: No cost
- O2 sensor replacement: No cost
- Exhaust repair: No cost
- Catalytic converter replacement: No cost
Out-of-Warranty Reference
- Catalytic converter: $750–$1,400
- O2 sensor: $150–$280
- Exhaust leak repair: $100–$300
DIY Considerations
Do not perform DIY repairs on a 2024 Compass. The vehicle is under full warranty.
Cost Breakdown Summary
- Under warranty: $0
- OEM converter (future reference): $400–$900
- O2 sensor (future reference): $55–$150
Prevention Tips
- Follow Stellantis maintenance schedule for the new 2.0L turbo engine
- Use the recommended oil grade for the turbocharged engine
- Keep all service records for warranty documentation
- Address check engine lights promptly
- Use quality fuel — turbo engines benefit from higher-octane fuel