Understanding dashboard warning lights in your Audi A4 is essential for keeping you safe on the road, as they alert you to potential issues that could lead to accidents or breakdowns. These lights help with timely vehicle maintenance, preventing small problems from turning into costly repairs.
By knowing what each one means, you can take quick action to protect yourself and extend your car’s life.
Quick Navigation
Red (Stop Immediately)
Brake System
This light signals a problem with the brakes, like low fluid or a system failure. Stop the car safely right away and call for help to avoid accidents.
Engine Oil Pressure
It warns of low oil pressure or high engine heat. Pull over, turn off the engine, check the oil level, and do not drive until fixed.
Battery/Alternator
This indicates a charging system issue, such as a failing battery or alternator. Stop driving soon, as the car may lose power completely; get it checked immediately.
Seatbelt Reminder
It reminds you or passengers to buckle up. Fasten all seatbelts before driving to ensure safety in case of a crash.
Airbag System
This shows a fault in the airbags or seatbelt tensioners. Stop and have it inspected, as safety features may not work in an accident.
Coolant Temperature
It means the engine is overheating or coolant is low. Stop the vehicle, let it cool, check coolant levels, and seek service to prevent damage.
Power Steering
This alerts to a failure in the steering system. Pull over safely, as steering may become hard; contact a mechanic right away.
Central Indicator
A general alert for serious issues; check other lights or messages. Stop driving and investigate or get professional help.
AdBlue Level
For diesel models, it means AdBlue fluid is critically low. Refill immediately or the engine may not start; visit a service center.
Steering Lock
This indicates a malfunction in the electronic steering lock. Do not turn off the engine, as restarting may fail; seek assistance.
Key Warning
It signals a problem with the engine start system. Keep driving to a safe spot but get serviced soon, as you may not restart.
Bonnet Open
This warns that the hood is not closed properly. Stop and secure it to avoid it flying open while driving.
Door Ajar
It means a door is not fully closed. Pull over, check and close all doors securely before continuing.
Transmission Overheat
This shows the transmission is too hot. Stop the car, let it cool, and have it checked to prevent failure.
Yellow/Amber (Action Required Soon)
ABS
This light means the anti-lock braking system has a fault. Brakes still work but without anti-skid; get it checked soon for safety.
Tyre Pressure
It warns of low pressure in one or more tires. Check and inflate tires promptly to avoid blowouts or poor handling.
Glow Plug
For diesel engines, it signals an issue with starting or emissions. Have the system inspected soon to fix any faults.
DPF
This indicates the diesel particulate filter needs attention, like regeneration. Drive at higher speeds or visit a service center to clear it.
ESP
It shows the electronic stability program is off or faulty. Turn it on if possible, or get serviced to maintain control on slippery roads.
Check Engine
This alerts to an engine or emissions problem. Scan for codes and visit a mechanic soon to prevent bigger issues.
Transmission
It means a gearbox issue, like slipping or overheating. Limit driving and have it diagnosed quickly.
Brake Pad Wear
This warns that brake pads are worn thin. Replace them soon to keep braking effective and safe.
Low Fuel
It indicates fuel is running low. Refuel at the next station to avoid running out.
Washer Fluid
This shows low windshield washer fluid. Refill it soon for clear visibility.
Lamp Out
It means a bulb, like headlights or taillights, is burnt out. Replace the bulb promptly for safe driving.
Coolant Low
It means coolant level is dropping. Top it up and check for leaks before serious overheating occurs.
Green (Information Only)
Turn Signal
This blinks to show turn signals are on. No action needed unless it flashes fast, meaning a bulb check.
High Beam
It indicates high beam headlights are active. Switch to low beams when oncoming traffic appears.
Cruise Control
This shows cruise control is engaged and maintaining speed. Adjust as needed for your drive.
Eco Mode
It means eco driving mode is on, saving fuel. No action required; it optimizes efficiency.
Lane Assist Active
This confirms lane assist is working, helping keep you in your lane. Drive normally.
Front Fog Lights
It shows front fog lights are on for better visibility in fog. Turn off when not needed.
Rear Fog Lights
This indicates rear fog lights are active. Use in heavy fog and switch off otherwise.
Auto High Beam
It means automatic high beams are functioning. They adjust for traffic automatically.
Hill Descent Control
This shows the system is on, controlling speed on steep hills. Use for off-road descents.
Direction Indicators
These flash for signaling turns or hazards. Ensure they work for safe communication.
Start/Stop System
It indicates the engine auto-stop is active for fuel savings. It restarts when you move.
Recirculated Air
This shows cabin air is recirculating. Good for keeping out outside smells.
Winter Mode
It means the transmission is in winter setting for better traction. Use in snow.
Speed Limiter
This confirms the speed limit is set and active. Helps control maximum speed.
EV Mode
For hybrid models, it shows electric-only driving is on. Switches automatically.
When looking at Audi, make sure to check out our guides on models like the Audi A1, Audi TT, Audi Q5, and Audi A3. Understanding dashboard warning lights is essential. Our expert reviews break down what each light means, highlighting common alerts for these models and what they could signal about underlying issues, so you’re never left guessing behind the wheel.
