What Does the P0351 Code Mean? The P0351 code indicates that the powertrain control module (PCM) detects an issue with the cylinder #1 ignition coil or its circuit. The ignition coil works like a transformer. It contains two coils., The diagnostic trouble code is the code your OBD generates to tell you something is wrong. Reading as a series of five letters and numbers, the DTC allows you to hone in on the system that is not functioning properly., To read OBD codes for cars made after 1996, you’ll first need to purchase an OBD-II scanner and connect it to your car’s Diagnostic Link Connector, which you can find by consulting either the internet or your owner’s manual., If you own a car, knowing how to read car diagnostic codes can save you time, money, and unnecessary trips to the mechanic. These codes help you understand what’s wrong with your vehicle before attempting a repair or seeking professional help., Car diagnostic codes, or OBD-II codes, are numerical and alphanumeric codes generated by your vehicle’s onboard diagnostics system. They serve as a language between your car and a diagnostic tool, making it easier for mechanics to identify issues., Ignition system fault codes definition (P0300 ‡ P0399) used in the OBD2 norm..