If you are investigating oil residue around the engine, save every stored and pending code before clearing anything. An OBD scan rarely identifies an oil leak; warning lights and level checks matter more. Record the engine temperature and load alongside the reading; the same value can mean different things in different conditions.
A basic reader may not access every module. Check whether the residue is fresh, where it begins, and whether the oil level is changing. Use the exact vehicle’s service information to interpret the result.
Quick educational note
For information, not a diagnosis or repair instruction. Vehicle-specific checks are still required. Consult the manufacturer's guidance and a qualified technician.
How to use this information
This article explains general principles and does not establish what is wrong with your vehicle. Read the content limitations.