Audi A4 Owners Manual
Warning and indicator lampsControls / Instruments and warning/indicator lamps / Warning and indicator lamps
Overview
The warning and indicator lamps indicate a number of different functions and possible faults.
Instrument cluster with warning and indicator lamps
Additional warning and indicator lamps are displayed on vehicles equipped with the adaptive cruise control*.
Note
A number of functions are monitored by the auto-check control. If a malfunction should occur, this will be shown by the display in the instrument cluster either with a red symbol (priority 1 – serious malfunction) or a yellow symbol (priority 2 – other malfunction or item requiring attention).
Dynamic steering
If the warning lamp lights up when
If the warning lamp stays on after
WARNING
Have the system malfunction in the dynamic steering repaired by a qualified workshop as soon as possible – risk of accident.
Note
- • If the warning lamp
flashes, this indicates that
the dynamic steering is being initialised. The message “Dynamic steering: Initialising” ⇒ page 36 will appear in the driver information system display. - • The stabilisation functions of the dynamic steering are not available in the event of a system malfunction.
Engine management
This warning lamp monitors the engine management system on petrol engines.
The warning lamp (Electronic Power
Note
If the warning lamp lights up while the vehicle is moving, this indicates a fault in the engine management system. The engine should be serviced by a qualified workshop without delay.
Glow plug system
The indicator lamp lights up to show that the glow plugs are preheating.
Your vehicle is equipped with an automatic glow plug system.
The indicator lamp lights up while
Note
- • If the glow plug indicator lamp should start flashing while the vehicle is moving, this indicates a fault in the engine management system. The engine should be serviced without delay.
- • If the indicator lamp fails to light up when the ignition is switched on, this can mean that the glow plug system is defective. The engine should be serviced.
Electronic stabilisation program (ESP)
This warning lamp monitors the electronic stabilisation program.
The warning lamp has the following
- • It flashes when the ESP or traction control system (ASR) intervenes while the vehicle is in motion.
- • The warning lamp will light up continuously if the ESP or the traction control system (ASR) has been switched off using the ESP OFF button.
- • It lights up when the ignition is switched on and should go out again after about 2 seconds. This signals that the lamp is working properly.
- • It will light up continuously if there is a malfunction in the ESP.
- • It will also come on if a fault should occur in the ABS because the ESP operates in conjunction with the ABS.
If the battery has been disconnected, if the battery voltage is very low, or if the engine has been started from an outside power source, the ESP system will perform an initialisation of the various on-board sensors while you drive the first few metres. The warning lamp will light up during this period. It will go out when the initialisation has been completed.
If the warning lamp lights up and stays on after the engine is started, this may mean that the control system has temporarily switched off the ESP. In this case the ESP can be reactivated by switching the ignition off and then on again. If the warning lamp goes out, this means the system is fully functional.
For further information on the ESP.
Airbag system
This warning lamp monitors the airbag and seat belt tensioner system.
The warning lamp should light up
If the warning lamp does not go out, or if it lights up, flashes or flickers when the vehicle is moving, this indicates a malfunction in the system. This is also the case if the warning lamp does not light up when the ignition is switched on.
WARNING
If a malfunction should occur, have the system checked immediately by a qualified workshop. If this is neglected, there is a risk that the airbag system and/or belt tensioners may not be activated in an accident.
Tyre pressure monitoring
The tyre pressure should be corrected as soon as possible if it is too low.
If the symbol flashes for about
Turn signals
Depending on which turn signal is operated, either the left
or right
If one turn signal should fail, the indicator lamp will start flashing twice as fast.
This does not apply when towing a caravan or trailer. The indicator lamp will stop flashing if one of the turn signals on the vehicle or the caravan/trailer should fail. For further information on the turn signals.
Trailer turn signals
The indicator lamp flashes when the turn signals are operated while towing a caravan or trailer.
The indicator lamp flashes when
The indicator lamp will not flash if one of the turn signals on the trailer fails.
Seat belt warning lamp
The warning lamp acts as a reminder to fasten the seat belts.
After switching on the ignition, the warning lamp
will remain lit until the driver and
For further information on the seat belts.
Emission control system
If the warning lamp lights up continuously
If the warning lamp flashes drive on at reduced speed and seek professional help in order to avoid damage to the catalytic converter.
For further information on the catalytic converter. Applies to vehicles: with lane assist
lane assist (active)
The indicator lamp confirms that
For more information on the lane assist system, please see.
lane assist (inactive)
The warning lamp indicates that
Main beam headlights
The indicator lamp lights up when
Cruise control
The indicator lamp in the instrument
Anti-lock brake system (ABS)
The warning lamp monitors the ABS and the electronic differential lock (EDL).
The warning lamp lights up for a
There is a fault in the ABS if:
- • the warning lamp does not
light up when the ignition is switched on, - • the warning lamp does not go out again after a few seconds,
- • the warning lamp lights up when the vehicle is moving.
The vehicle can still be braked in the normal way (except that the ABS control function is out of action). Please take the vehicle to a qualified workshop as soon as possible. For further information on the ABS.
If a fault occurs in the ABS, the ESP warning lamp will also light up.
Fault in the main brake system
If the ABS warning lamp lights up
If there is a malfunction in the brake system the symbol
will light up in the instrument cluster.
Fault on the electronic differential lock (EDL)
The EDL works in conjunction with the ABS. If a malfunction should occur in the
EDL, this is indicated by the ABS warning lamp
. Please take the vehicle to a qualified
WARNING
- • Before opening the bonnet and checking the brake fluid level, observe the warning information on, “Working on components in the engine compartment”.
- • If the brake warning lamp
should light up together
with the ABS warning lamp , stop the vehicle immediatelyand check the brake fluid level in the reservoir. If the fluid level has dropped below the "MIN" mark you must not drive on - otherwise there may be an increased accident risk. You should obtain professional assistance. - • If the brake fluid level is OK, the fault in the brake system may have been caused by a failure of the ABS control function. As a result the rear wheels can lock relatively easily when braking. This could cause the tail of the vehicle to skid sideways. Drive carefully to the nearest qualified workshop and have the fault rectified.
Audi hold assist
This warning lamp monitors the Audi hold assist function. Audi hold assist helps
the driver to keep the vehicle stationary while the engine is running, for instance
on steep gradients, at traffic lights or in stop-and-go traffic. When the Audi hold
assist function is on, you don't have to keep your foot on the brake to prevent
the vehicle from accidentally rolling away. Once it detects that the vehicle is
stopped, Audi hold assist keeps the vehicle stationary. The green symbol
in the instrument cluster indicates
When the vehicle has been stationary for an extended period, Audi hold assist
will automatically apply the parking brake. In this case, the green symbol
will change to red
Electro-mechanical parking brake
This warning lamp monitors the electro-mechanical parking brake.
The warning lamp lights up when
The warning lamp should go out when the parking brake is released.
If the warning lamp flashes continuously after the parking brake has been applied, the brake may not be strong enough to hold the vehicle on a slope. This may be due to the brakes overheating. Please note the following points:
- • If the gradient is too steep to park the vehicle safely, the display will show the message Caution: Vehicle parked too steep.
- • In the event of a fault in the parking brake system the symbol
will also appear in the instrument
cluster display together with the message Parking brake! You should have the fault corrected by a qualified workshop without delay.
Brake system
The warning lamp flashes if the brake fluid level is too low or if there is a fault in the ABS system or the parking brake.
If the warning lamp flashes, there
WARNING
- • Before opening the bonnet and checking the brake fluid level, observe the warning information on, “Working on components in the engine compartment”.
- • If the brake warning lamp does not go out, or if it lights up when driving, the brake fluid level in the reservoir is too low – this may cause an increased accident risk. Stop the vehicle and do not drive on. You should obtain professional assistance.
- • If the brake warning lamp lights up together with the ABS warning lamp, this can mean that the control function of the ABS is out of action. As a result the rear wheels can lock relatively easily when braking. This could cause the tail of the vehicle to skid sideways. Drive carefully to the nearest qualified workshop and have the fault rectified.