Check engine light on - what it means

A warning light rarely means you need to stop the car immediately, but it shouldn't be ignored - it usually points to one specific sensor or control unit.

Possible causes

  • Check engine light - most often an oxygen sensor, spark plug, or fuel system sensor
  • ABS light - a wheel speed sensor or an ABS module fault
  • A light that stays on with no other symptoms - often just a sensor, not a costly part

An OBD scanner reads the exact fault code, so you know which part to replace instead of guessing.

Related parts

Control units and modulesDashboard

Read the full guide