Mercedes-Benz vehicles are packed with advanced sensors designed to keep you safe and informed. But when a mysterious dashboard symbol lights up, most drivers are left guessing: Is it urgent? Is it safe to drive? Do I need a mechanic now?
This comprehensive guide explains over 20 Mercedes dashboard symbols, what they mean, how serious they are, and what action (if any) you should take. Bookmark this for future reference or use it when that next icon appears on your dash.
Understanding Colours
Before diving into specific icons, it helps to know what the colours mean:
- Red = Stop immediately. Serious safety issue or potential damage.
- Yellow/Amber = Caution. Something needs attention soon.
- Green/Blue = Informational. System is active or working.
Red Warning Lights (Immediate Attention)
1. Brake Warning Light
Symbol: Circle with exclamation mark or the word “BRAKE”
Meaning: Parking brake engaged, low brake fluid, or brake system fault.
Action: If the parking brake is off and the light remains on—stop driving and get the brakes inspected.
2. Engine Temperature Warning
Symbol: Thermometer in liquid
Meaning: Engine is overheating.
Action: Pull over, shut off the engine. Check coolant once cool. Continuing to drive risks engine damage.
3. Battery/Charging System
Symbol: Battery icon
Meaning: Battery isn’t being charged—alternator or belt issue likely.
Action: Drive to a safe location with minimal electrical use. Get vehicle inspected immediately.
4. Airbag or SRS Warning
Symbol: A person with a circle in front of them
Meaning: Airbag or seatbelt tensioner fault.
Action: Airbags may not deploy in a crash. Have it checked ASAP.
5. Brake Pad Wear Indicator
Symbol: Circle with dotted lines on either side
Meaning: Brake pads are worn past limit.
Action: Get pads replaced immediately to avoid rotor damage.
6. Seatbelt Reminder
Symbol: Person with seatbelt
Meaning: Seatbelt is unfastened while the vehicle is in motion.
Action: Buckle up.
Yellow/Amber Warning Lights (Caution)
7. Check Engine Light (Malfunction Indicator Lamp)
Symbol: Outline of engine
Meaning: Emissions or engine system fault
Action: If steady, safe to drive short-term. Book diagnostics. If flashing, stop driving—could indicate misfire.
8. ABS Warning
Symbol: Circle with “ABS”
Meaning: Anti-lock braking system fault
Action: Brakes will still work, but ABS won’t. Avoid hard braking, get it checked.
9. ESP / BAS Warning
Symbol: Car with skid marks
Meaning: Electronic Stability Program or Brake Assist issue
Action: Vehicle stability systems may be disabled. Drive carefully and get diagnostics.
10. Tyre Pressure Monitoring System (TPMS)
Symbol: Horseshoe with exclamation point
Meaning: One or more tyres underinflated or sensor fault
Action: Check and correct pressure. If light remains, have sensors tested.
11. Glow Plug Warning (Diesel Only)
Symbol: Coil or wire spiral
Meaning: Preheating for diesel engine, or fault if it stays on/flashes
Action: Wait for light to go off before starting. If persistent, service needed.
12. Traction Control Light
Symbol: Car with squiggly lines
Meaning: Traction control active, or fault if permanently on
Action: If flashing during acceleration, normal. If steady, traction system fault—check soon.
13. Low Fuel Warning
Symbol: Fuel pump
Meaning: Fuel level critically low
Action: Refuel immediately. Running dry can damage fuel pump, especially in diesels.
14. Oil Level/Pressure Warning
Symbol: Oil can
Meaning: Low oil level or oil pressure
Action: Stop engine. Check oil. If level is fine and light stays on, call for assistance—pressure may be low.
15. Diesel Exhaust Fluid (AdBlue)
Symbol: Fluid bottle or “DEF”
Meaning: AdBlue/DEF low or system fault
Action: Refill AdBlue soon. If ignored, car may refuse to start.
16. Service Reminder
Symbol: Wrench or spanner
Meaning: Routine service due soon
Action: Book a service. Not urgent, but don’t ignore for months.
Green or Blue Lights (System Active)
17. High Beam Indicator
Symbol: Blue headlight with lines
Meaning: High beams are on
Action: Normal. Switch off if other drivers are approaching.
18. Cruise Control Active
Symbol: Speedometer with arrow
Meaning: Cruise control is engaged
Action: Informational only.
19. Fog Light Indicators
Symbol: Lamp with horizontal line and slashes (rear = amber, front = green)
Meaning: Fog lights are on
Action: Turn off in clear conditions to avoid dazzling others.
20. Start/Stop System Status
Symbol: Circular arrow with A in the center
Meaning: Automatic start/stop system active or paused
Action: Normal, unless system is failing to engage/disengage as expected.
Other Symbols Worth Knowing
21. Convertible Roof Warning (SLK, CLK, E-Class Cabrio)
Symbol: Car with top opening or triangle with roof
Meaning: Roof not fully secured or fault in mechanism
Action: Stop and re-secure roof or seek service.
22. Parking Assist / Parktronic
Symbol: P with waves
Meaning: Obstacle detection active or unavailable
Action: Clean sensors. If still faulty, inspect system.
23. Bulb Failure Indicator
Symbol: Light bulb with line through it
Meaning: One or more exterior bulbs have failed
Action: Replace bulb or check for connection fault.
24. Hybrid/Electric System Warning (for EQ and hybrid models)
Symbol: Electric bolt or battery icon with warning
Meaning: Fault in battery system
Action: Stop driving and get professional inspection.
Final Tips: What to Do When a Light Appears
- Don’t panic. Check your manual or this guide.
- Take note of the light colour and behaviour. Flashing lights usually mean more urgency.
- Combine symptoms. Warning lights + strange sounds/smells = act quickly.
- Use STAR diagnostics. For Mercedes, generic code readers often miss key data.
- Never ignore red lights. These indicate serious safety or mechanical issues.
When to Call a Specialist
If a red or flashing yellow warning light appears, or if multiple systems light up at once, don’t guess. Mercedes systems are interconnected, and faults in one area often affect others.
Always get your car scanned with STAR or XENTRY diagnostics—only available at authorised Mercedes-Benz dealers or qualified specialists.
Summary: Mercedes Warning Lights at a Glance
- Red = Stop now (brakes, overheating, airbags, oil pressure)
- Yellow = Service soon (check engine, ESP, tyre pressure, DEF)
- Green/Blue = Info only (lights, cruise, start/stop)
Don’t ignore the lights—understand them. A quick response can save you money and protect your car.
