Information about AdBlue

AdBlue consumption rates on your Seat Leon will vary depending on individual driving style, vehicle load, operating temperatures of the exhaust aftertreatment system, and the prevailing outdoor ambient temperature.

Aqueous urea solution (AdBlue) freezes at a temperature of -11 ºC (+13 ºF). To prevent freezing issues, the vehicle is equipped with automated heating elements that guarantee proper system operation and fluid flow even during severe winter conditions.

When the remaining driving range drops below 2,000 or 2,400 km (approx. 1,200 or 1,500 miles), depending on your specific vehicle version and powertrain calibration, an automated prompt will appear on the instrument cluster display requesting an AdBlue top-up.

If this initial warning message is disregarded, a yellow indicator light will illuminate once the remaining operating range falls below 1,000 km (approx. 600 miles) . Concurrently, a notification stating that engine restarting will be disabled in a specified number of kilometres or miles will appear on the instrument cluster display screen.

If this yellow indicator warning is ignored and the remaining driving range reaches 0 km (0 miles), it will no longer be possible to restart the engine once switched off. At this point, a red warning light will illuminate to signal a lockout.

AdBlue is a registered trademark of the German Association of the Automotive Industry (VDA) and is widely recognized internationally under the alternative designations AUS32 or DEF (Diesel Exhaust Fluid).

NOTICE Overfilling the AdBlue reservoir beyond its rated capacity can cause high fluid pressure and permanent structural damage to the tank and filler system architecture.

Fill AdBlue

Fig. 212 AdBlue tank cap.

Operations prior to refilling

Park your Seat Leon on a flat, level surface and completely switch off the ignition. If the vehicle is parked on an incline, a slope, or tilted up on a kerb, the electronic fluid level sensor may fail to detect the newly added AdBlue quantity accurately.

If an active AdBlue low-level warning message is currently displayed on your instrument cluster, you must replenish the tank with at least the minimum required threshold amount (approximately 5 litres).

Only after pouring in this minimum fluid volume will the onboard sensor system successfully recognize that AdBlue has been added, allowing you to start the engine again without restriction.

Fill with a refill bottle

Only use AdBlue fluid that complies strictly with the ISO 22241-1 quality standard.

• Always use original containers and approved filler bottles.
• Open the outer fuel and AdBlue tank flap ››› Fig. 212.
• Unscrew the internal AdBlue tank filler cap by turning it in an anticlockwise direction.
• Carefully observe all safety and handling instructions indicated by the manufacturer on the refill bottle label.
• Check the expiration date printed on the container before use.
• Remove the protective cap from the refill bottle.
• Insert the neck of the refill bottle vertically into the vehicle tank filler neck and screw the bottle securely into place by hand, turning it clockwise until tight.
• Press the refill bottle downward in the direction of the filler neck and maintain it firmly in this position.
• Wait patiently until the entire contents of the refill bottle have drained completely into the AdBlue tank. Do not squeeze, puncture, compress, or break the plastic bottle!
• Rotate the bottle in a counter-clockwise direction to disengage it, then gently pull it straight upwards out of the neck.
• The AdBlue tank is full when fluid stops flowing and no more liquid empties from the bottle.
• Screw the tank cap back on in a clockwise direction until it is tightly sealed and clicks shut.
• Close the outer fuel tank flap flush with the bodywork.

Refilling AdBlue at the dispenser

Valid for vehicles equipped with selective catalytic reduction (SCR).

• Open the outer tank flap.
• Turn the SCR tank filler cap anti-clockwise to remove it ››› Fig. 212.
• Fill with AdBlue using the service station pump nozzle until the automatic shut-off valve stops the flow for the first time.
• Close the SCR filler tube securely by turning the cap clockwise until you hear a distinct click.

Operations before driving

• After completing the AdBlue refill process, switch on only the vehicle ignition without cranking the engine.
• Leave the ignition switched on for a minimum of 30 seconds to allow the control module and fluid sensors to detect the new fluid load.
• Make sure you wait for at least 30 seconds before attempting to start the engine!

WARNING AdBlue solution should always be stored exclusively in its original, sealed container, which must be tightly closed and kept in a secure, well-ventilated place out of reach of children.

NOTICE

• When refilling AdBlue on your Seat Leon at a service station pump, ensure that the dispensing nozzle grip and handle are oriented and aligned pointing downward. If positioned incorrectly, the automatic shut-off and locking mechanism will fail to connect properly.
• Never attempt to force or add any additional AdBlue fluid after the pump nozzle has automatically stopped for the first time. Overfilling the tank can cause the AdBlue reservoir to overflow, leading to corrosive fluid spilling onto the vehicle bodywork.
• Only use AdBlue fluid that complies strictly with the ISO 22241-1 quality standard. Always use genuine original containers and certified fluid products.
• Never mix AdBlue with water, fuel, engine oil, or any unauthorized chemical additives.

  Any mechanical or chemical damage resulting from such an improper fluid mixture is strictly excluded from vehicle warranty coverage.

• Never pour AdBlue fluid directly into the vehicle's fuel tank! Doing so will result in catastrophic, irreparable damage to the fuel system and engine.
• Do not transport spare AdBlue refill bottles inside the passenger cabin of your Seat Leon. If a leak occurs due to ambient temperature fluctuations or container damage, the highly corrosive fluid can cause permanent stains and structural damage to the vehicle's interior trim and carpeting.

For the sake of the environment

Always dispose of empty AdBlue refill bottles and packaging materials in an environmentally responsible, compliant manner.

Note Original, certified AdBlue refill bottles compatible with your Seat Leon can be purchased directly from authorized SEAT dealerships and service partners.

Troubleshooting

AdBlue level too low

The indicator lamp lights up red. The engine cannot be restarted! Stop your Seat Leon safely in a suitable, level area away from active traffic, then top up the tank with at least the minimum required quantity of AdBlue fluid.

together with : Fault in the AdBlue system

The control lamps light up red. The engine cannot be restarted! Go to a specialized workshop immediately and have the emission control system checked and diagnosed.

together with : Fault in the AdBlue system

The control lamps light up red. The engine cannot be restarted! Go to a specialized professional workshop and have the AdBlue system inspected without delay.

together with : Fault in the AdBlue system.

The control lamps light up yellow. This indicates either a malfunction within the selective catalytic reduction system or that non-conforming, uncertified AdBlue fluid has been added to the tank. Go to a specialized workshop and get the system inspected immediately.