The lights and icons on your Audi A4 dashboard warn you about problems or give information. They matter because ignoring them can lead to car damage or even a crash. For example, a red brake light might mean your brake fluid is low – if you keep driving, you could lose braking power.
A yellow check engine light could mean something is wrong with the engine; driving with it on can cause more damage. Paying attention to these symbols helps keep yourself safe and avoid costly repairs.
Audi A4 Dashboard Light Colors: Red, Yellow, Green Explained:
Dashboard symbols use colors like traffic lights. Red lights mean they will stop soon – the problem is urgent. For example, the red brake warning means stopping safely and fixing the brakes. Yellow or amber lights indicate a warning or that service is needed soon.
You don’t need to stop the car immediately but address the issue promptly. If you notice a yellow engine or oil warning light, it indicates that you should have your engine or oil inspected at the earliest opportunity.
Green lights (and blue sometimes) are informational, showing a system is on or okay (like headlights on or cruise control active). Always check your owner’s manual for exact meanings, but remember: red = urgent, yellow = caution, and green/blue = normal status.
Brake System Lights:
1. Parking Brake / Brake Fluid Warning (Red Circle with “P” or Exclamation):
This light is red. It often resembles a circle with an exclamation mark or a (P) inside. This indicator illuminates when the parking brake is engaged, the brake fluid level is low, or there’s an issue within the braking system.
If it stays on after releasing the parking brake, pull over and inspect the brakes immediately—there could be a fluid issue or brake failure. If this warning appears alongside the ABS light, it signals a severe brake system failure. Stop driving right away and have the vehicle towed for service.
Action: Safely stop the car. Ensure the parking brake is released, and check the brake fluid level (if you know how). If the light stays on, do not drive – call a mechanic or roadside help immediately.
2. ABS Warning (Yellow “ABS”):
This light shows the letters ABS (Anti-lock Braking System) in yellow. ABS helps you keep control if you brake hard. If the ABS light comes on, your regular brakes will still work without anti-lock help. You can keep driving slowly, but get it fixed soon.
However, the brake system is unsafe if the ABS light appears simultaneously with the red brake warning light. In that case, stop driving immediately and get help.
Action: If only ABS is on, drive carefully with extra space and have a shop check the ABS soon. If the brake light is on too, stop immediately and have the car inspected.
3. Brake Pad Wear (Yellow/Red Brake Pad Icon):
This symbol resembles a circle or oval with dashed lines (representing the brake pad) and clips. It might glow yellow or red. It means the brake pads are thin and need replacing soon. Audi fits sensors in the pads that turn this light on before they wear out completely.
Action: Consider replacing your brake pads as soon as possible. Although you still have some braking ability, braking becomes dangerous if the pads wear out fully.
4. Electronic Brake Distribution (EBD):
Often labeled as “EBD” or associated with the ABS. If this light comes on, it indicates a problem with the brake force distribution system. It usually appears alongside the ABS or brake warning lights.
Action: Treat it like a brake problem – get it checked by a mechanic soon.
Engine and Power System Lights:
1. Check Engine / Engine Malfunction (Yellow Engine Icon):
This light usually looks like a side view of an engine. It can also be labeled “CHECK” or “MIL.” It can mean many things: a bad sensor, a spark plug, an emission problem, or other engine faults. The RAC notes that when this light is on, your engine may run rough or lose power. It is often yellow.
Action: As soon as you see it, have your car checked. Driving further with it on can cause significant damage. If it comes on suddenly with a dramatic change (smoke, noise, power loss), stop safely and seek help. Otherwise, drive gently to a garage for diagnostics.
2. Electronic Power Control (EPC) Warning (Yellow “EPC”):
The EPC light shows the letters EPC (Electronic Power Control) in yellow. It means the engine’s computer detected a fault in systems like throttle, cruise control, traction, or fuel injection. When EPC lights up, the car may go into “limp mode” (low power mode) to protect itself.
Action: If the EPC comes on, slow down and drive to a safe place. It’s best to pull over safely as soon as possible and have it inspected right away. The RAC advises driving to a garage (or home if close) immediately because limp mode means performance is reduced, and unresolved faults could harm the engine further.
3. Oil Pressure/Level (Yellow/Red Oil Can Icon):
This symbol looks like an old-fashioned oil can with a drip. It can be yellow or red. It means the engine oil pressure is low, the oil level is low, or the oil is too hot. Oil lubricates and cools the engine; engine parts can grind and get ruined without it.
Action: If this comes in red, stop driving immediately. Turn off the engine and check the oil level (when cool). Add oil if needed and check for leaks. If it’s yellow and steady, you still should stop soon. Don’t drive more until you fix the oil problem, as continuing to drive can cause engine damage.
4. Coolant Temperature (Red Thermometer Icon):
Usually, a red thermometer in liquid or thermometer over squiggle means the engine is overheating. A small glow means warm; if it glows or blinks red, the engine is too hot. Causes include low coolant (leak), a stuck fan, or even a broken head gasket.
Action: If it’s red, stop driving immediately. Allow the engine to cool completely before checking—never open the radiator cap while it’s still hot. Once cooled, inspect the coolant level and top it off if it’s low. If the engine continues to overheat or you notice leaks, seek professional help immediately. Operating a vehicle with an overheated engine can cause severe internal damage, potentially fusing metal components beyond repair.
5. Battery/Charging (Red Battery Icon):
This icon shows a battery shape, usually in red. It indicates a failure in the charging system—your battery isn’t replenished. Possible causes include a faulty alternator, a snapped belt, or a failing battery. Until the issue is fixed, the vehicle will rely solely on battery power, eventually running out.
Action: If this lights up while driving, try to reach a safe place soon. Keep the engine running to preserve power, but head to a garage quickly. If the battery drains, the car will stall (no lights or control). If it happens at night or far from help, consider calling for roadside assistance.
6. Diesel Particulate Filter (DPF) (Yellow/Red “DPF” Icon):
If your A4 has a diesel engine, you may see a “DPF” light or a symbol of a filter. It means the soot filter in the exhaust is clogged. A blocked filter can cause black smoke and engine problems.
Action: Usually, the car will try to clear it by running a “regen” (heating the filter). If it stays on, go to a garage. Avoid short trips; driving longer highway distances can help burn off soot. But if it’s flashing or red, have it cleaned or replaced at a service center.
7. Glow Plug (Diesel Glow Plug Light):
On diesel models, you might see an orange icon that looks like a coiled wire or “glow plug.” When you start the car (red or orange) to heat the plugs, it usually comes on and then goes off. It means a glow plug or emission issue if it stays lit or comes on while driving.
Action: You can still drive a little, but get the engine checked soon. If the light starts flashing, stop and get help. Neglecting it may result in more serious engine issues down the line.
8. Engine Immobilizer (Key or Lock Symbol):
When the system is armed, some A4s have a flashing key or lock icon. The car’s anti-theft system does not recognize your key if it stays on or blinks.
Action: Try another key. If it still won’t recognize, the car may not start. You’d need dealer help or a reprogramming of the key.
Tire Pressure and Traction Lights:
1. Tire Pressure (Yellow Horseshoe with Exclamation):
This symbol looks like a flat tire shape with an exclamation point in the middle. It means one or more tires are too low (or, in rare cases, too high) in pressure. Audi’s TPMS (Tire Pressure Monitoring System) automatically checks your tire pressure. If it lights up, inflate your tires to the correct pressure (sticker on the door jamb) soon. The RAC explains that low pressure can cause unsafe handling or a blowout.
Action: You can keep driving carefully for a short time, but slow down and fill the tires as soon as possible. Check each tire for punctures or leaks. A properly inflated tire lasts longer and saves fuel.
2. Stability/Traction Control (Yellow “ESP” or Car Skid):
This symbol is often a car with curvy skid marks or the letters ESP (Electronic Stability Program) or DSC. If it blinks while driving, it means ESP is active (helping you grip). If it stays on, the system has an issue. If turned off, it could also say “ESP OFF.”
Action: If it just blinks during a skid, that’s normal (it’s helping). If it stays on, try restarting the car. If the light remains, get it checked. You can still drive but must be extra careful on slippery roads without stability control.
3. Traction Control Off (Often the same as ESP):
Some Audis show a crossed-out version of the stability icon or say “TC OFF.” This means the Traction Control is turned off.
Action: You will have a regular grip without help. That’s fine in dry conditions, but turn it back on or slow down if rain or ice comes. You can keep going, but remember that your traction is limited.
Safety and Restraint System Lights:
1. Airbag / SRS Light (Red Airbag Icon):
This light looks like a person seated with a round airbag in front, or it might say SRS. It’s red. If it lights up and stays on, the airbags or seatbelt pre-tensioners aren’t working correctly.
Action: Do not drive long with this light on. The airbags might not deploy in a crash or could deploy incorrectly. Get to a garage immediately to diagnose the problem.
2. Seat Belt Reminder (Red Person with Belt Icon):
A red icon of a seated figure with a belt means someone’s seat belt isn’t fastened. It is often accompanied by a chime. CarParts explains that it flashes if it detects an empty seat or unbuckled belt.
Action: Buckle your seat belt! The light and sound will stop. If the belt is fastened and the light stays on, check if something is on the passenger seat (like a heavy bag) or if a sensor is faulty.
3. Pre-Sense System (Yellow/Red Diamond or “Pre-Sense”):
Newer Audis have Audi Pre-Sense (a safety pre-crash system). The sensors or system faults if its symbol (often a yellow/red car icon or diamond) appears.
Action: The car will still drive, but advanced safety features (like emergency braking) won’t work correctly. Take it to the dealer soon to have this system fixed.
4. Suspension Control (Yellow Car on Springs Icon):
This icon looks like a car with springs or an “ACT” or “adaptive suspension” text. It means that the adjustable suspension system has an error. You might feel the ride is bumpy or the car sits low.
Action: Drive carefully to a mechanic. A faulty suspension can make handling unpredictable. It’s not an emergency to stop immediately, but don’t ignore it.
Indicators and Other Symbols:
These lights show normal functions or minor issues but are good to know:
- High Beam (Blue Headlight Icon): A blue light with rays means the high-beam (main) headlights are on. This is normal. Turn them off if approaching other cars.
- Turn Signals (Green Arrows): Blinking green arrows on the left and right show that your turn signals or hazards are on—normal behavior.
- Headlights/Daytime (Green Headlight Icon): A green symbol of a lamp means your low-beam headlights or daytime running lights are on. Just informational.
- Fog Lights (Green/Amber Lamp Icon): A green icon (with lines and waves) means front fogs are on; amber is for rear fogs. This is to remind you they’re active.
- Door/Bonnet Open (Red Car with Door): A red icon of a car with an open door or hood means one door or the trunk/bonnet isn’t closed. Action: Pull over safely and close it. For a bonnet (hood) warning, the RAC warns that a gust could lift the hood while driving, so fix it immediately.
- Fuel Low (Yellow Gas Pump): A yellow pump means low fuel. Refuel soon.
- Service or Wrench (Yellow/Orange Spanner): This service reminder or maintenance light means the car is due for a scheduled service (oil change, inspection, etc.). It’s not urgent like red, but don’t ignore it.
Action: Book a service soon. Regular maintenance avoids breakdowns – for example, not changing oil can wear the engine faster.
- Washer Fluid (Yellow Windshield Symbol): This symbol resembles a windshield with wipers and spray. It means the washer fluid is low. Top up the fluid.
- Parking Assist / Sensors (Yellow “P” with sound waves): This means a parking sensor or assist system has a fault. It is often not urgent unless you rely on it.
- Immobilizer/Key (Red Key Icon): A flashing or red key symbol means the key isn’t recognized or there’s an ignition lock issue. The car might not start. Try a spare key or get dealer help.
- Air Conditioning / Seat Heaters (Green “A/C” or seat icon): These are green and show that those systems are on.
Each symbol has a specific shape. If you see an unfamiliar icon, refer to the owner’s manual. The manual will show each symbol exactly as on your cluster.
What to Do When a Light Comes On:
- Stay Calm: Don’t panic. Many lights mean “check soon,” not “stop now.”
- Assess Urgency: Red lights usually mean stop safely and fix. Yellow lights mean service or fix soon. Green/blue lights are typically standard info.
- Check Gauges: If an engine or temperature light comes on, check the temperature gauge or oil gauge (if available). This can confirm if the engine is hot or the oil is low.
- Read Messages: Some A4 models also display a text message (in the MMI or driver display) explaining the warning.
- Address Quickly: Don’t just turn off the light. Fix the issue. For example, if the low oil light comes on, add oil, not just clear the light.
- Use a Mechanic: Many problems need a pro. If a light stays on or returns, have the car inspected.
Helpful Tips: Keep an eye on your gauges and lights daily. Follow service intervals (oil changes, filters). Check tire pressure once a month. These habits can prevent many warning lights. If a warning comes up, safely find a place to pull over and troubleshoot if you can (like checking under the hood). It’s always safer to immediately address a warning than to risk a breakdown.
Frequently Asked Questions:
Q1. Can I drive my Audi A4 with the check engine light on?
Yes, but only if the car feels normal and the light is steady (not flashing). A flashing check engine light usually signals a serious problem like a misfire—stop driving and get help. Even with a constant light, you should have the issue diagnosed and repaired as soon as possible to avoid damage.
Q2. What can the red oil light mean?
A red oil warning light signals dangerously low oil pressure, which can lead to severe engine damage in minutes. Pull over right away, shut off the engine, and check the oil level. If it’s low, add more oil. If the warning light remains on, do not continue driving—have the vehicle towed to a qualified mechanic.
Q3. How do I reset the service light in my Audi A4?
Depending on your model year, you can often reset the service reminder using the buttons on the instrument cluster or through the MMI system. However, it is best to reset it only after completing the required service. Check your owner’s manual or ask a technician for guidance.
Q4. What should I do if the tire pressure light comes on?
Check the pressure of all four tires and inflate them to the recommended PSI (found in the driver’s door jamb or manual). If the warning light remains illuminated even after adjusting the tire pressure, you might need to reset the TPMS system manually. However, if the light flashes, it could signal a sensor malfunction that requires a technician’s diagnosis.
Q5. Why is the EPC light on, and what does it mean?
The EPC (Electronic Power Control) light signals a problem with the throttle, traction, or engine management systems. The car may enter limp mode and lose power. You can usually still drive short distances, but you should have the system scanned and repaired as soon as possible.
Conclusion:
Understanding the dashboard symbols in your Audi A4 is essential for staying safe, preventing breakdowns, and extending your vehicle’s life. Each light gives real-time feedback on your car’s condition—from critical engine or brake warnings to simple reminders like low washer fluid or an open door.
By learning what each symbol means and how to respond, you can drive more confidently and avoid costly repairs. Always treat red and flashing lights urgently, and don’t ignore yellow warnings for too long. When in doubt, consult your owner’s manual or a qualified mechanic. Keeping your dashboard clear of warning lights is one of the easiest ways to ensure your Audi stays in peak condition.
