2021 VOLKSWAGEN UP! check engine

General information on the heating and fresh air system
First read and observe the introductoryinformation and safety warnings⇒
Introduction
The required interior temperature cannot be lower than the outside temperature as the heating and
fresh air system cannot cool or dehumidify the air.
Settings for optimal road visibility
•Set blower ⇒ Fig. 112② to level 1 or 2.
•Open and position all vents on the dash panel ⇒ Vents.
•Turn the air distribution controller ⇒ Fig. 112③ to the defrost position.
Information on the air conditioning system
First read and observe the introductoryinformation and safety warnings⇒
Introduction
The cooling system for the vehicle interior only works when the engine is running and the blower is
switched on.
The air conditioning system operates most effectively with the windows and the electric panorama
sliding and tilting glass roof closed. However, if the vehicle has heated up after standing in the sun
for some time, the air inside can be cooled more quickly by opening the windows and the electric
panorama sliding and tilting glass roof for a short time.
Settings for optimal road visibility
Switching the cooling system on not only reduces the temperature of the vehicle interior, but also
the humidity. This improves comfort for the vehicle occupants and prevents the windows from
misting when the outside humidity is high.
•Switch off air recirculation mode ⇒ Air recirculation mode.
•Set the blowers to the required level.
•Open and position all vents on the dash panel ⇒ Vents.
•Turn the air distribution controller to the defrost position.
•Press the button to switch the cooling system on. The indicator lamp in the button
lights up.
The cooling system cannot be switched on
The following criteria may prevent the cooling system from being switched on:
•The engine is not running.
•The blower is switched off.
•The air conditioning system fuse has blown.
•The ambient temperature is lower than approximately +2℃ (+36°F).
•The compressor has been temporarily switched off because the coolant temperature is too high.
•There is a different fault in the vehicle. The air conditioning system should be checked by a
qualified workshop.
Things to note
If the humidity and temperature outside the vehicle are high, condensation can drip off the
evaporator in the cooling system and form a pool underneath the vehicle. This is normal and does
not indicate a leak.
The windscreen may mist up after starting the engine due to residual humidity in the air
conditioning system. Switch the defrost function on in order to clear the windscreen of condensation
or mist as quickly as possible.
Vents
Fig. 114 In the dash panel: vents
First read and observe the introductoryinformation and safety warnings⇒
Introduction

Fig. 115 In the instrument cluster: variant A: fuel gauge for petrol, variant B: fuel gauge for petrol
Fig. 116 In the instrument cluster display: fuel gauge for petrol
First read and observe the introductoryinformation and safety warnings⇒
Introduction
The fuel gauge can vary according to the vehicle equipment level ⇒ Fig. 115 or ⇒ Fig. 116.
Lit upNeedle position
⇒ Fig. 115
Possible cause ⇒Solution
Red marking ①
Fuel tank nearly empty.
Reserve quantity is being used
⇒ Capacities.
Fill the tank with petrol
as soon as possible ⇒
.
Blue marking ②
Natural gas fuel tank nearly
empty.
Reserve quantity is being used.
Refuel with natural gas
as soon as possible ⇒
.
Flashes for
approximately
10 seconds
Position of the
bar ⇒ Fig. 116
Possible cause ⇒Solution
Reserve fuel
marking flashes for
approximately 10
seconds (four small
segments)
Fuel tank nearly empty.
Reserve quantity is being used
⇒ Capacities.
Fill the tank as soon as
possible ⇒.
Several warning and indicator lamps will light up briefly as a functional check when the ignition is
switched on. They will switch off after a few seconds.
Natural gas engines
Things to note: if the vehicle is parked for an extended period directly after refuelling, it may well
occur that the pointer for the natural gas engine does not indicate the fuel level shown directly after
refuelling. This does not mean that there is a leak in the system but but rather that, for technical
reasons the pressure has been decreased in the natural gas tank.
The small arrow next to the petrol pump symbol ⇒ Fig. 115 in the display instrument shows
you the side of the vehicle on which the tank flap is located.
Only applies for vehicles with a fuel gauge in the instrument cluster ⇒ Fig. 115.
Only applies for vehicles with a fuel gauge in the instrument cluster display ⇒ Fig. 116.
Filling the tank with petrol
a)
b)
Driving the vehicle when the fuel level is too low could lead to your vehicle breaking down in
traffic, accidents and serious injuries.
•When the fuel level is too low, the fuel supply to the engine could be irregular, especially
when driving up or down hills and inclines.
•The steering, all driver assist systems and brake assist systems will not function if the
engine sputters or stops completely due to a lack of fuel or irregular fuel supply.
•Always fill the tank when it is still 1/4 full. This reduces the risk of running out of fuel and
breaking down.
WARNING
•To avoid damage to your vehicle, always observe the indicator lamps and associated
warning texts.
•Do not run the tank empty. Irregular filling periods can cause backfiring and allow unburnt
fuel to enter the exhaust system. This could cause damage to the catalytic converter!
NOTICE
a)
b)

Switch off the engine, ignition and the mobile telephone before filling the tank and leave them
switched off during the process ⇒.
Please read and follow the instructions for the natural gas refuelling system.
The vehicle is not constructed for use with Liquefied Natural Gas (LNG) ⇒. Before refilling with
natural gas check that you are using the correct fuel ⇒ Fuel.
Opening the tank cap
The gas filler neck is located under the tank flap next to the petrol filler neck.
•The tank flap is at the rear of the vehicle on the right.
•Open the tank cap by the moulding to the rear.
Filling the tank
At very high ambient temperatures, the overheating protection function for the natural gas refuelling
system could switch off automatically.
•Remove the cap ⇒ Fig. 118① from the gas filler neck ②.
•Place the filler coupling for the refuelling system on the gas filler neck. Please refer to natural
gas refuelling system operating manual.
•The fuel tank is full when the compressor for the refuelling system switches off automatically.
•To end the refuelling procedure press the stop button on the refuelling system.
Closing the tank cap
•Check whether seal ⇒ Fig. 118③ on the gas filler neck has slipped onto the filler coupling.
Place the seal back in the gas filler neck as necessary.
•Push the cap ① onto the gas filler neck.
•Close the tank flap. The tank flap must be flush with the vehicle bodywork.
The filling couplings for the natural gas refuelling systems can be of various different
designs. Please ask for assistance from trained personnel if you are unsure of how to use the
system.
Noises which you may hear while refuelling are normal and do not indicate that the system is
malfunctioning.
The natural gas system in your vehicle is suitable for use with small compressors (slow fill)
and large compressors (fast fill).
Capacities
First read and observe the introductoryinformation and safety warnings⇒
Introduction
Fuel tank capacity
Petrol enginesapprox 35.0 l, of which 4.0 l reserve.
Natural gas engineNatural gas: approx. 11.0 kg of which reserve approx. 1.5 kg.
Petrol: approx. 10.0 l of which reserve approx. 5.0 l
Checks when filling the tank
First read and observe the introductoryinformation and safety warnings⇒
Introduction
Checklist
Never carry out any work on the engine or in the engine compartment if you are not familiar with
the necessary procedures and the general safety requirements or if the correct operating
Natural gas is highly explosive and inflammable. Failure to refuel properly with natural gas
could result in accidents, serious burns and other injuries.
•Lock the fuel filler nozzle correctly before refuelling natural gas. Stop refuelling
immediately if you start to smell gas.
WARNING
Your vehicle is not suitable for use with Liquefied Natural Gas and must not be filled up or
driven with Liquefied Natural Gas. Liquefied Natural Gas can cause an explosion in the
natural gas tank and serious injuries as a consequence.
WARNING

Windscreen washer fluid level Windscreen wiper and washer
Engine oil level Engine oil
Engine coolant level Coolant
Brake fluid level Braking, stopping and parking
Tyre pressure Wheels and tyres
equipment, service fluids and unsuitable tools are not available ⇒ Preparation for working in the
engine compartment! The work should be carried out by a qualified workshop if you are
uncertain. Please ensure that the following are checked regularly, preferably every time you fill
the tank:
Vehicle lighting necessary for traffic safety:
- Turn signals
- Side lights, dipped beam headlights and main beam headlights
- Tail light cluster
- Brake lights
- Rear fog light ⇒ Lights
Information on changing bulbs ⇒ Changing bulbs.
Fuel
 Introduction
This chapter contains information on the followingsubjects:
⇒ Petrol
⇒ Natural gas
Different engines require different fuels. The factory-fitted sticker on the inside of the tank flap
indicates the fuel type that is required for your particular vehicle.
Volkswagen recommends using low-sulphur or sulphur-free fuels, to help reduce fuel consumption
and prevent damage to the engine.
If the engine is not running smoothly or begins to judder, this can indicate poor or inadequate fuel
quality, e.g. water in the fuel. If these symptoms appear, reduce the vehicle speed immediately and
drive to the nearest qualified workshop at medium engine speeds, avoiding high engine loading. If
these symptoms occur immediately after the vehicle has been refuelled, switch the engine off as
soon as it is safe to do so and seek expert assistance. This can help to prevent further damage.
Additional information and warnings:
•⇒BookletService schedule,
•Filling the tank ⇒ Filling the tank
•Engine management and exhaust system ⇒ Engine management system and exhaust
purification system
Petrol
First read and observe the introductoryinformation and safety warnings⇒
Introduction
Petrol types
Vehicles with a petrol engine must be run on unleaded petrol in compliance with the European
standard EN 228 or DIN 51626-1 ⇒. Fuels with a maximum ethanol content of 10% (E10) can
be used for refuelling.
Petrol types are categorised according to their octane number, e.g. 91, 95, 98 or 99 RON (RON =
Research Octane Number). The vehicle may be filled with petrol that has a higher octane number
Incorrect handling of fuel can cause explosions, fire and serious burns and injuries.
•Fuel is highly explosive and inflammable.
•Never handle fuel near open flames, sparks or glowing matter (e.g. cigarettes).
•Keep naked flames, hot parts and sparks at a safe distance.
•Switch off your mobile telephone or two-way radio when dealing with fuel. Electromagnetic
radiation can generate sparks which can in turn start a fire.
•Avoid electrostatic discharge and electromagnetic radiation in the direct vicinity of fuels.
•Never spill fuel in the vehicle or in the luggage compartment.
•Comply with any relevant safety information and legislation concerning the handling of
fuels.
WARNING

than the engine requires. However, this does not provide any advantage in terms of fuel
consumption or engine output.
Volkswagen recommends using fuel with a low sulphur content or sulphur-free fuel for petrol
engines in order to achieve reduced fuel consumption.
Petrol additives
The quality of petrol influences the running properties, performance and service life of the engine.
This is why the vehicle should be refuelled with good quality petrol that has only non-metallic
additives pre-added by the petroleum industry. These petrol additives help to prevent corrosion,
keep the fuel system clean, and prevent the build-up of deposits in the engine.
If good quality petrol containing non-metallic additives is not available, or if engine problems arise,
the necessary petrol additives must be added to the petrol when refuelling ⇒.
Not all petrol additives are effective. The use of unsuitable petrol additives can cause considerable
damage to the engine and catalytic converter. Metallic additives should be avoided at all times.
Petrol additives on sale that are intended to improve knock resistance or increase the octane
number can also contain metallic additives ⇒.
Volkswagen recommends genuine Volkswagen or Audi fuel additives for petrol engines. These
additives and information on how to use them are available from your Volkswagen dealership.
Natural gas engines
Run the petrol tank empty every 6 months until the indicator lamp  lights up. This is necessary to
maintain the required system function for petrol mode and fuel quality.
Natural gas
First read and observe the introductoryinformation and safety warnings⇒
Introduction
Natural gas
Natural gas can be delivered in compressed or liquefied form.
Liquefied Natural Gas (LNG) is produced by rapid cooling of the natural gas. This decreases the
volume considerably in comparison to Compressed Natural Gas (CNG). A vehicle equipped with a
natural gas engine may not be refilled directly with liquefied natural gas as the gas would expand
too much once in the tank in the vehicle.
Vehicles fitted with a natural gas engine may therefore only be refilled and driven using
compressed natural gas ⇒.
Natural gas quality and consumption
Natural gas is available in two grades: H-gas and L-gas.
H-gas has a higher calorific value and a lower nitrogen and carbon dioxide content. The higher the
calorific value of the natural gas the lower the levels of consumption.
The calorific value and the nitrogen or carbon dioxide values may, however, vary within one quality
group. For this reason, the vehicle consumption may vary when using natural gas of the same
quality.
•Before filling up with petrol, check whether the fuel corresponds to the vehicle's
requirements according to the fuel standard information at the pump.
•Only use fuel that complies with EN 228 or DIN 51626-1 and has the correct octane
number. Otherwise, the engine and the fuel system can suffer considerable damage. The
engine can also lose power or fail.
•The use of unsuitable petrol additives can cause considerable damage to the engine and
catalytic converter.
•If, in an emergency, you have to use petrol with an octane number lower than the
recommended number, drive at medium engine speeds and avoid high engine loading.
Avoid high engine speeds and heavy engine loads. Failure to do so can result in engine
damage. Fill the tank with petrol with the correct octane number as soon as possible.
•Fuels that are identified at the fuel pump as containing metallic additives may not be used.
LRP fuel (lead replacement petrol) also contains high concentrations of metallic additives.
Risk of engine damage!
•Just one tankful of leaded fuel, or fuel containing other metallic additives, can seriously
impair the efficiency of the catalytic converter and can also cause considerable damage to
the catalytic converter and engine.
NOTICE

The vehicle engine management will automatically adapt to the different natural gas qualities. Both
natural gas qualities can therefore be mixed in the fuel tank. You do not need to empty the tank
before refuelling with a different grade.
Natural gas
The vehicle can run on natural gas. Further information is available from your local Volkswagen
dealership.
Safe handling of natural gas
If you can smell gas or think there may be a leak in the natural gas system ⇒:
•Stop the vehicle immediately.
•Switch off the ignition.
•Open all the doors to fully ventilate the vehicle.
•Extinguish cigarettes immediately.
•Remove items that could cause sparks or fire from the vehicle or switch them off.
•Do not drive on if you can still smell gas.
•Seek expert assistance. Have the fault rectified.
Have the natural gas system checked regularly according to the service schedule by a
qualified workshop.
In the engine compartment
Preparation for working in the engine compartment
 Introduction
This chapter contains information on the followingsubjects:
⇒ Preparing the vehicle for working in the engine compartment
⇒ Opening and closing the bonnet
Always park the vehicle on a level and stable surface before carrying out any work in the engine
compartment.
The engine compartment of a motor vehicle is a hazardous area. Never carry out any work on the
engine or in the engine compartment if you are not familiar with the requisite procedures and
general safety requirements, or if you only have access to incorrect operating equipment, service
fluids, and unsuitable tools ⇒. The work should be carried out by a qualified workshop if you are
uncertain. Serious injuries can be caused if work is carried out incorrectly.
Additional information and warnings:
•Exterior views ⇒ Exterior views
•Windscreen wiper/washer ⇒ Windscreen wiper and washer
•Starting and stopping the engine ⇒ Starting and stopping the engine
•Brake fluid ⇒ Braking, stopping and parking
•Checks when filling the tank ⇒ Filling the tank
•Engine oil ⇒ Engine oil
•Engine coolant ⇒ Coolant
•Battery ⇒ Vehicle battery
•Accessories, modifications, repairs and renewal of parts ⇒ Accessories, modifications, repairs
and renewal of parts
Ignoring the smell of gas in the vehicle or when refuelling can cause serious injuries.
•Take any necessary action.
•Leave the area of risk.
•Contact the emergency services if necessary.
WARNING
Your vehicle is not suitable for use with Liquefied Natural Gas and must not be filled up or
driven with Liquefied Natural Gas. Liquefied Natural Gas can cause an explosion in the
natural gas tank and serious injuries as a consequence.
WARNING
Cleaning and maintenance

Park the vehicle on a level and stable surface.
Depress and hold the brake pedal until the engine has stopped.
Apply the handbrake firmly Braking, stopping and parking.
Select the neutral position or move the selector lever to N Changing gear.
Stop the engine and remove the vehicle key from the ignition Starting and stopping the
engine.
Allow the engine to cool sufficiently.
Children and other people should be kept well away from the engine compartment.
Ensure that the vehicle cannot roll away unexpectedly.
Service fluids leaks are harmful to the environment. So you should regularly check the
ground underneath your vehicle. If there are spots of oil or other fluids on the ground, the vehicle
should be inspected by a qualified workshop. Any spilt service fluids must be disposed of properly.
Preparing the vehicle for working in the engine compartment
First read and observe the introductoryinformation and safety warnings⇒
Introduction
Checklist
The following steps should always be carried out in the specified order before working in the
engine compartment ⇒:
There are rotating components in the engine compartment that can cause serious injury.
•Never place your hand near or directly in the radiator fan. Touching the rotary blades can
result in serious injuries. The fan is temperature-controlled and can start automatically,
even if the engine has been switched off and the vehicle key has been removed from the
ignition lock.
•If any work has to be performed when the engine is started or with the engine running,
there is an additional, potentially fatal, safety risk from the rotating parts, such as the drive
belts, alternator, radiator fan, etc., and from the high-voltage ignition system. Always be
particularly careful.
- Always ensure that no body parts, jewellery, ties, loose items of clothing or long hair
can be caught up in rotating engine components. Before starting work, remove any
jewellery and ties, tie up long hair and pull clothes in tightly to avoid them getting
caught in the engine compartment.
- Always depress the accelerator carefully and never without due consideration. The
vehicle can start to move even if the handbrake is applied.
•Always ensure that you have not left any objects, such as cleaning cloths and tools, in the
engine compartment. Any forgotten items can cause malfunctions, engine damage and
fires.
WARNING
Operating fluids and some materials in the engine compartment are highly flammable and can
cause fires and serious injuries!
•Never smoke while working on the vehicle.
•Never work near naked flames or sparks.
•Never spill fluids onto the engine. They could ignite on hot engine components and hence
cause injuries.
•Please note the following when carrying out any work on the fuel system or the electrical
system:
- Always disconnect the vehicle battery.
- Never work in the direct proximity of heating systems, water heaters or any other
open flames.
•Always have a fully functional and tested fire extinguisher to hand.
WARNING
When refilling or changing operating fluids please ensure that the fluids are in the correct
container. Incorrect operating fluids can cause serious functional problems and engine
damage.
NOTICE

Engine oil
 Introduction
This chapter contains information on the followingsubjects:
⇒ Warning and indicator lamps
⇒ Engine oil specification
⇒ Checking the engine oil level and refilling engine oil
⇒ Engine oil consumption
⇒ Changing engine oil
Additional information and warnings:
•⇒BookletService schedule,
•Preparation for working in the engine compartment ⇒ Preparation for working in the engine
compartment
•Accessories, modifications, repairs and renewal of parts ⇒ Accessories, modifications, repairs
and renewal of parts
Leaking or spilt engine oil can pollute the environment. Spilt operating fluids must be
collected and disposed of properly and with respect for the environment.
Warning and indicator lamps
First read and observe the introductoryinformation and safety warnings⇒
Introduction
FlashesPossible causeSolution
Engine oil pressure is too low.
Do not drive on!
Switch off the engine. Check the engine oil
level.⇒ Checking the engine oil level and
refilling engine oil
– Do not drive on or remain at idling speed
if the warning lamp is flashing, even if the
engine oil level is correct. The engine could
otherwise be damaged. Seek expert
assistance.
Engine oil specification
First read and observe the introductoryinformation and safety warnings⇒
Introduction
The engine oil used must correspond exactly to specifications.
The correct engine oil is important for the function and service life of the engine. A special high
quality multigrade oil has been filled at the factory and this can normally be used as an all-season
oil.
Incorrect handling of engine oil can cause serious burns and injuries.
•Always wear eye protection when handling engine oil.
•Engine oil is toxic and must be stored out of the reach of children.
•Engine oil must be kept in the closed original container. This also applies to used oil until it
is disposed of.
•Never use empty food containers, bottles or other containers to store engine oil as other
people may then drink the engine oil.
•Regular contact with engine oil can damage the skin. Skin that has been in contact with
engine oil should be washed thoroughly with water and soap.
•Engine oil becomes extremely hot when the engine is running and can scald skin severely.
Always allow the engine to cool down.
WARNING
Failure to observe the warning lamps could lead to your vehicle breaking down in traffic, and
to accidents and serious injuries.
•Never ignore any warning lamps that are lit up.
•Stop the vehicle as soon as possible and when safe to do so.
WARNING
Failure to observe the illuminated indicator lamps could lead to the vehicle being damaged.
NOTICE