P0421

The P0421 code indicates that the engine control module (ECM) has detected a warm-up catalytic converter efficiency problem, specifically on a BMW X5 G05 (2019-2024).

The P0421 code indicates that the catalyst efficiency for Bank 1 is below the threshold level in a 2014-2019 BMW X5 F15, suggesting potential issues with the catalytic converter, oxygen sensors, or exhaust system.

The P0421 code in a BMW X5 G05 (2019-2024) indicates an issue with the warm-up catalyst efficiency for bank 1, suggesting that the catalytic converter is not performing as expected.

The P0421 code in a 2014-2019 BMW X5 F15 indicates a problem with the warm-up catalyst efficiency below the threshold for bank 1. This typically suggests an issue with the catalytic converter or related components.

The P0421 code indicates that the catalytic converter's efficiency is below the threshold on a 2019-2024 BMW X5 G05. This typically suggests potential issues with the catalytic converter, oxygen sensors, or exhaust leaks.