Honda Civic O2 Sensor Code Not Clearing Due to Power Issue in Heater Wire on Honda Civic

Some Honda Civic owners report experiencing persistent O2 sensor codes that do not clear due to power issues in the heater wire. These issues may stem from a lack of power to the heater element of the downstream O2 sensor, specifically related to the BLK/YEL wire in models like the DX or LX with a D17A1 engine. Additionally, owners may encounter symptoms such as decreased fuel efficiency, rough idling, and potential stalling, which are associated with a malfunctioning O2 sensor heater circuit. The P0135 diagnostic trouble code (DTC) is often indicative of a power supply malfunction for the O2 sensor heater circuit. For those using aftermarket O2 sensors, improper wiring can lead to damage to the ECU, so verifying correct wiring and ensuring the heater power wire receives battery voltage is crucial. Furthermore, if an error code like P0141 appears, it is advisable to inspect the electrical system for faults, including short circuits, open circuits, and loose connections. Addressing these power issues promptly can help resolve the ongoing O2 sensor code concerns.