Gauges and warning lights are the driver’s window into the vehicle’s condition. Understanding them prevents damage, improves safety and keeps the car reliable. For a broader overview of the vehicle’s systems, see Vehicle components.
Core gauges in the cluster
| Gauge | Function | Typical scale |
|---|---|---|
| Speedometer | Displays road speed | km/h |
| Tachometer (RPM) | Shows engine speed | rev/min |
| Fuel gauge | Indicates remaining fuel | 0-100 % |
| Temperature gauge | Monitors coolant temperature | deg C or C/H |
| Oil pressure gauge | Shows engine oil pressure | Bar or warning zone |
Dashboard warning lights
Warning lights alert you to abnormal conditions. Follow the owner’s manual and stop if required.
| Warning light | Meaning |
|---|---|
| Engine (Check engine) | Engine management has detected a fault, from emissions to ignition issues |
| Oil pressure | Oil pressure is low; stop the engine as soon as it is safe |
| Battery/charging | Alternator or battery is not charging |
| Brake system | Low brake fluid, brake fault or parking brake engaged |
| ABS | Anti-lock system fault; brakes work without ABS support |
| Coolant temperature | Coolant is overheating; stop and check the cooling system |
| Tyre pressure | Tyre pressure monitoring detects low or uneven pressure |
| Airbag | Airbag or belt pretensioner fault; have the safety system inspected |
For typical brake faults see Brake failures. For tyre pressure information read Tyre pressure and TPMS. Engine related warnings are explained in Engine lights and indicators.
Colour codes and what to do
| Colour | Example | Action |
|---|---|---|
| Red | Oil pressure, coolant temperature | Stop safely, switch off the engine and troubleshoot |
| Amber | Check engine, TPMS | Drive carefully to a workshop and check levels or pressures |
| Blue/Green | High beam, daytime running lights | Information only, no action needed |
Power-on lamp test
Most lamps illuminate briefly at ignition for a self-test and should switch off after a few seconds. A lamp that stays on means you need to investigate further.
How to respond when a lamp turns on
- Stay calm and observe: Identify the colour and symbol.
- Check the owner’s manual: Confirm the meaning and recommended action.
- Stop if required: For red lamps or unusual noises, pull over and shut the engine off.
- Do basic checks: Verify oil, coolant and brake fluid levels before continuing.
- Read fault codes: Use an OBD-II reader to understand engine warnings, see OBD-II code reader.
- Seek professional help: Contact a workshop if the lamp persists.
Digital clusters and head-up displays
Modern cars use digital instrument clusters and head-up displays (HUD) to show speed, navigation and driver-assistance warnings.
- Safe HUD setup is covered in Head-up display (HUD).
- Distance alerts link to Autonomous emergency braking (AEB).
- Cruise distance control is part of Adaptive cruise control (ACC).
Display tips:
- Show only necessary data to avoid distraction
- Position HUD graphics so they do not hide critical objects in view
- Keep phone mounts or dashcams from blocking the projected area
Summary
Understanding the instrument cluster keeps you proactive about maintenance, cuts repair costs and improves safety. For further reading see Vehicle maintenance, ABS (anti-lock braking system) and Tyre pressure and TPMS.