Description and operation

Not valid for PHEV hybrid vehicles

 Only applicable in vehicles equipped with Keyless Access.

 In the mHEV mild-hybrid version of the Seat Leon, this function is operational above 20 km/h.

The intelligent Start-Stop system helps you to save fuel efficiently and reduce tailpipe CO2 emissions during everyday urban driving.

In Start-Stop mode, the engine will automatically switch off when the vehicle comes to a stop or is actively slowing down to a halt. The ignition system remains fully switched on throughout the stop phase, and the engine automatically restarts when required.

During this operating scenario, the status light on the control button remains lit.

Whenever the ignition is switched on, the Start-Stop function is automatically activated by default.

Control lamps

The Start-Stop system is available, and automatic engine shutdown is active.

The Start-Stop system is not available or has been disconnected.

Stopping and starting the engine

Vehicles with a manual gearbox:

• When the vehicle is brought to a stop, shift the transmission into neutral and release the clutch pedal fully. The engine will automatically stop to save fuel. The warning lamp will light up on the cluster display. Note that the engine may even shut down before the vehicle comes to a complete standstill (at approximately 7 km/h).
• When you depress the clutch pedal again to prepare to move, the engine will start instantly, and the indicator lamp will go out.

Vehicles with an automatic gearbox:

• Brake until your Seat Leon comes to a complete standstill, and keep your foot firmly on the brake pedal or ensure the Auto Hold function is engaged so that the vehicle remains braked. The engine will stop automatically, and the warning lamp will appear on the display.

  The engine may switch off before the vehicle comes to a complete standstill (at approximately 7 or 2 km/h, depending on the specific vehicle gearbox configuration).

• When you lift your foot off the brake pedal, the engine will start up again immediately and the indicator lamp will go out. However, when the Auto Hold system is active, the engine will not restart simply by removing your foot from the brake; instead, the car starts smoothly as soon as you press the accelerator pedal.

Basic requirements for the start/stop mode

• The driver's door must be completely closed.
• The driver's seat belt must be securely fastened.
• The bonnet must be fully closed.
• The engine has reached its required operating temperature.
• Reverse gear must not be engaged.
• The vehicle must not be parked or travelling on an extremely steep slope.

The engine does not turn off for various reasons

Before bringing the vehicle to a halt, the management system verifies whether specific operating parameters are met. The engine will not switch off automatically in situations such as the following:

• The engine has not yet reached the required operating temperature for Start-Stop operation.
• The target interior temperature selected on the climate control panel has not yet been achieved.
• Maximum defrosting (HI) or minimum cooling (LO) temperature is requested in the air conditioner.
• The windscreen de-icing function button is activated.
• Park assist is currently switched on and active.
• The 12-volt battery charge level is very low.
• The steering wheel is turned sharply to an extreme angle or is actively being turned.
• There is an active risk or danger of window misting.
• Reverse gear was recently engaged.
• The vehicle is negotiating a very steep gradient.
• In heavy traffic jams after the engine has stopped and restarted five consecutive times in succession, the engine will temporarily stop shutting down automatically.
• Electronic Stability Control (ESC) is disabled.
• Following an emergency braking manoeuvre or a sudden loss of tyre adhesion.
• When a trailer is electrically connected and attached to the vehicle.
• While the particulate filter is currently undergoing self-cleaning regeneration.

The instrument cluster screen of your Seat Leon displays .

The engine starts by itself

When the vehicle is stopped in Start-Stop mode, normal system operation may be interrupted automatically under certain conditions. In these instances, the engine will restart by itself without requiring any direct intervention from the driver.

• The internal cabin temperature deviates significantly from the target temperature selected on the climate control panel.
• The windscreen defrost function button is manually activated.
• The brake pedal is pumped or pressed several times in rapid succession, reducing brake system pressure.
• The 12-volt vehicle battery charge level drops below the minimum required threshold.
• There is an exceptionally high electrical power consumption demand from onboard systems.
• The vehicle begins to roll forward or backward while the engine is currently switched off.
• Electronic Stability Control (ESC) is deactivated.
• On vehicles equipped with a manual gearbox: the accelerator pedal is depressed by the driver.

Additional information related to the automatic gearbox

On automatic models, the engine stops automatically when the gear selector lever is positioned in D, N, or S, as well as while driving in manual Tiptronic mode. Furthermore, when the parking lock button P is engaged, the engine will also remain switched off even if you remove your foot entirely from the brake pedal.

In mHEV mild-hybrid Seat Leon versions, automatic engine shutdown does not occur when the transmission selector is in position S or while operating in manual Tiptronic mode.

In order to start the engine up again and prepare for movement, the accelerator pedal must be pressed, a different gear selected, or the foot brake released.

If the transmission selector lever is shifted into reverse position R while the vehicle is stopped, the combustion engine will start up again immediately.

Additional information about vehicles with Adaptive Cruise Control (ACC)

In vehicles equipped with the Adaptive Cruise Control (ACC) function, the engine will start up again automatically in specific traffic conditions if the front radar sensor detects that the vehicle ahead of you has driven off again.

WARNING

• Never switch off the ignition or the engine until the vehicle has come to a complete, final stop. When the engine is off, the full hydraulic power assistance for the brakes and steering will not be guaranteed.

  Substantially more physical force will be required to turn the steering wheel or apply the brakes effectively. Losing control under these conditions could lead to severe accidents and serious injuries.

• To prevent accidental injury or burns, always ensure that the Start-Stop system is completely switched off before performing any maintenance or work inside the engine compartment of your Seat Leon.

NOTICE The Start-Stop system must always be switched off manually before attempting to drive through waterlogged or flooded areas.

Note

• In vehicles equipped with an automatic gearbox, you can actively control whether the engine switches off or stays running by modulating the amount of pressure applied to the brake pedal. While the vehicle remains stationary, the engine will not shut down if the brake pedal is only pressed lightly—such as during slow, stop-and-go traffic jams with frequent creeping.

  As soon as you apply firm, strong pressure to the brake pedal, the engine will cut out to save fuel.

• When the vehicle is stopped, the brake pedal must be kept firmly depressed to ensure that the car does not roll or move unexpectedly.
• If the engine "stalls" unexpectedly on a manual gearbox model, it can be restarted instantly and directly by immediately depressing the clutch pedal to the floor.
• If the transmission selector lever is moved back into position D, N, or S immediately after engaging reverse gear, the vehicle must first reach a forward speed of at least 10 km/h (6 mph) before the Start-Stop system is permitted to shut down the engine again.

Manually connecting and disconnecting the Start-Stop system

Not valid for PHEV hybrid vehicles

Fig. 122 In the infotainment system: Start-Stop system (accessible from different infotainment menus).

1. System disconnected.
2. System connected.

If you prefer not to use the automated engine shutdown feature during specific driving conditions, you can easily switch the system off manually:

• In the central infotainment system of your Seat Leon, select > Assistants > Smart Assistants.

Note Every time the ignition is switched back on, the Start-Stop system automatically reactivates itself by default.

Troubleshooting

Not valid for PHEV hybrid vehicles

Indications for the driver on the instrument cluster screen

A clear advisory warning message will be displayed on the screen whenever there is a system malfunction or when the Start-Stop system status is toggled on or off.

"Start the engine manually"

• This notification indicates that the Start-Stop system is unable to restart the engine automatically.

This situation typically occurs for two main reasons: either the driver's door has been opened, or the driver has unbuckled their seat belt while the engine was shut down.

"Start-Stop system: Fault! Function not available"

• A fault has been detected within the Start-Stop system circuitry or sensors. Take your Seat Leon to an authorized specialized workshop to have the issue diagnosed and repaired promptly.