There are several causes potentially related to the P013C code. The code commonly involves defective O2 sensors, meaning you must replace them. However, less commonly, you might experience this code due to engine exhaust leaks, issues with electrical wiring and connectors, problems with wiring harnesses and ground signals, or even a defective catalytic converter, although this will usually come with additional codes. If the electrical signal or voltage signal cannot reach the PCM, including problems with the O2 sensor voltage, it will log this code even though the O2 sensor readings are accurate. Most of the time, however, an O2 sensor will fail biased toward a lean voltage.

In most cases, you can drive with the P013C code active, as this code very rarely results in severe drivability issues. However, just because you can drive when the P013C code is active doesn’t mean you should. If the P013C code is active, you should do your best to address it as soon as possible, as allowing it to persist can do significant engine damage. Avoid driving with the P013C code.

Inspecting the P013C code can sometimes be difficult because plenty of issues can arise within this system and create problems. Specifically, many wiring issues arise to prevent reliable vehicle function, which you might need a wiring diagram and more than basic tools to tackle effectively. You may also need a diagnostic scanner, a digital volt/ohmmeter (DVOM), and access to technical service bulletins and other vehicle information sources, such as diagnostic notes, to inspect this code. If you’re not confident with your ability to perform more than a visual inspection, especially if you don’t know how to inspect the wiring, it might be best to talk to a certified mechanic to achieve successful repairs.