Can I Drive With the Check Engine Light On?
A steady lamp may allow a cautious trip for diagnosis, while a flashing lamp, major drivability change, overheating, oil-pressure warning, or unsafe behavior calls for stopping.
Tag diagnostic questions
Should I Clear Codes Before Diagnosis?
Usually no: clearing removes freeze frame, resets monitors, and can erase the operating context that makes an intermittent fault diagnosable.
Why Are Warning Lights On After Battery Replacement?
Low voltage, module resets, lost steering or window initialization, disconnected sensors, and new network codes can all appear after battery work.
What Live Data Should I Check First?
Start with a short list tied to the complaint; too many parameters slow sample rate and hide the relationship between command and response.
When Is a Compression Test Needed?
Compression testing becomes useful when misfire or no-start evidence points toward mechanical sealing or timing after ignition and mixture checks.