Understanding Engine Warning Lights
Home/Automotive Advice/Understanding Engine Warning Lights
Diagnostics25 July 2025· 5 min read

Understanding Engine Warning Lights

What does each dashboard warning light actually mean, and which ones need immediate action?

Modern vehicles monitor dozens of systems and illuminate warning lights when something needs attention. Knowing which lights are urgent and which can wait for a scheduled visit can save you money, and potentially your engine.

Red Warning Lights: Stop Driving

Red warning lights indicate a serious fault that requires immediate action. Do not continue driving. Pull over safely when possible and call for assistance.

  • Engine oil pressure (oil can symbol) — stop immediately and check oil level. Driving with low oil pressure can destroy an engine in minutes
  • Engine temperature (thermometer in water symbol) — coolant temperature is dangerously high. Stop, let the engine cool, and check the coolant level only when cold
  • Battery / charging (battery symbol) — alternator may have failed. The car will continue to run on battery power until it's exhausted, leaving you stranded
  • Brake system (exclamation mark in circle) — when the handbrake is off, this indicates a brake hydraulic system fault

Amber Warning Lights: Book a Check Soon

Amber lights indicate a fault that doesn't require immediate stopping but should be investigated promptly — within a few days.

  • Engine management light (engine outline) — a broad warning covering many possible faults. Diagnostic scan needed
  • DPF warning light (diesel particulate filter) — filter is becoming blocked. Longer motorway run may trigger regeneration; if light persists, book a diagnostic
  • TPMS (tyre pressure monitoring) — one or more tyres is significantly under-inflated. Check pressures
  • ABS warning light — anti-lock braking system has a fault. Brakes still work but ABS function is disabled
  • Traction control / stability control — system has a fault. Vehicle may be less stable in slippery conditions

Don't Ignore Warning Lights

Many drivers cover dashboard lights with tape or ignore them, hoping they'll go away. They won't — and the underlying fault will worsen. At PKA Automotive, we can carry out a diagnostic scan to read the exact fault codes causing any warning light and advise on the appropriate repair.

PKA

PKA Automotive Ltd

Expert car and commercial vehicle servicing, repairs, and maintenance in Keighley, West Yorkshire. Serving customers across West Yorkshire and beyond.