Check Engine Light
Urgency: ModerateThe check engine light is triggered when your vehicle's onboard diagnostic system (OBD-II) detects a problem with the engine, transmission, or emissions system. It can indicate anything from a loose gas cap to a serious engine misfire. The light may be steady (indicating a non-urgent issue) or flashing (indicating a severe problem that requires immediate attention).
Need to read your codes?
An OBD-II scanner lets you read and clear diagnostic trouble codes from your vehicle's computer. Most scanners work with any car made after 1996.
Browse OBD-II Scanners on AmazonPossible Causes
- Loose or faulty gas cap
- Failing catalytic converter
- Bad oxygen sensor
- Engine misfire
- EVAP system leak
- Mass air flow sensor failure
Related OBD-II Codes
When to See a Mechanic
If the light is flashing, pull over safely and have the vehicle towed. If steady, schedule an appointment within a week. Use an OBD-II scanner to read the specific code.
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