2012 VOLKSWAGEN PASSAT engine

Checking engine coolant level and topping off

Fig. 183 Coolant expansion tank in the engine compartment.

Fig. 184 Coolant expansion tank cap in the engine compartment.

Adding engine coolant
x Always protect face, hands and arms from hot escaping coolant or steam by covering the cap with a large, thick rag.
x Carefully unscrew the cap ⇒ .
x Add only new engine coolant according to Volkswagen specifications ( Engine coolant
specifications ) ⇒ .
x The engine coolant level must be inside the marks on the side of the reservoir . Do not fill above
the top edge of the filling range! ⇒ 
x Screw the lid tightly.
x Even in an emergency, do not use any other kind of coolant additive if engine coolant meeting
Volkswagen specifications (⇒ page 296, Engine coolant specifications) is unavailable! Instead, add
distilled water only ⇒ . As soon as possible, have the correct coolant ratio restored using engine
coolant that meets Volkswagen specifications ,Engine coolant specifications.
WARNING
Hot steam and hot engine coolant can cause serious burns.
x Never open the hood if you see steam or coolant escaping from the engine compartment. Always wait until you no longer see or hear steam or coolant escaping from the engine.
x Always let the engine cool down completely before carefully opening the hood. Hot components will burn skin on contact.
x When the engine has cooled down and you are ready to open the hood:
– Firmly apply the parking brake and shift the transmission into Park (P) (automatic) or Neutral (manual only).
– Take the vehicle key out of the ignition.
– On vehicles with Keyless Access, make sure that the remote control vehicle key is out of range of the vehicle and that the vehicle cannot be started by depressing the starter
button ⇒ page 205, Starter button.
– Always keep children and others away from the engine compartment and never leave them unsupervised.
x The engine coolant system is under pressure when the engine is hot. Never unscrew the coolant expansion tank cap when the engine is hot. Hot coolant can spray out and cause severe burns and other serious injuries.
– Turn the cap slowly and very carefully in a counterclockwise direction while applying light downward pressure on the top of the cap.
– Always protect your face, hands, and arms from hot escaping coolant or steam by covering the cap with a large, thick rag.
x Never spill fluids on the engine or exhaust system when refilling. Spilling fluids onto hot parts of the engine or exhaust system can cause a fire. Under some conditions, the ethylene glycol in engine coolant can catch fire.
NOTICE
x Use distilled water only when adding coolant! All other types of water contain chemical compounds that can cause extensive corrosion damage to the engine. This can even lead to engine failure. If you have added non-distilled water, take the vehicle immediately to an authorized Volkswagen dealer or an authorized Volkswagen Service Facility to have the coolant system drained, flushed, and refilled completely with the proper coolant.

x Refill engine coolant only up to the top edge of the marked fill range . Excess engine coolant may be forced out of the engine cooling system when it gets hot and cause damage.
x In the case of significant engine coolant loss, refill engine coolant only when the engine is completely cooled down. Significant engine coolant loss is a sign of leaks in the cooling system. Have the engine cooling system checked immediately by an authorized Volkswagen dealer or an authorized Volkswagen Service Facility. Otherwise the engine may be damaged!
x When changing or topping off operating fluids, make sure that you pour the fluids into the correct reservoirs. Serious malfunctions and engine damage can result if you pour operating fluids into the wrong reservoir.

x Preparations for working in the engine compartment
x Parts, accessories, repairs and modifications
WARNING
Working on the batteries or the electrical system in your vehicle can cause serious acid burns, fires, explosions, or electrical shocks. Always read and heed the following WARNINGS and safety precautions before working on the batteries or the electrical system.
x Before working on the electrical system, always switch off the ignition and all electrical consumers and disconnect the negative (-) cable from the standard 12 Volt battery.
x When you change a light bulb, always switch off the light first.
x Always keep children away from battery acid and vehicle batteries in general.
x Always wear eye protection. Never let battery acid or lead particles come into contact with your eyes, skin, or clothing.
x Sulfuric battery acid is very corrosive. It can burn unprotected skin and cause blindness. Always wear protective gloves and eye protection. To reduce your risk of injury, never tilt the batteries, as this could spill acid through the vents and burn you.
x If you get battery acid in your eyes or on your skin, immediately rinse with cold water for several minutes and then get immediate medical attention. If you swallow any battery acid, get medical attention immediately.
x When disconnecting the batteries from the vehicle electrical system, always disconnect the negative cable (-) first and then the positive cable (+).
x Always switch off all electrical consumers before reconnecting 12 Volt batteries. Reconnect the plus cable (+) first and then the negative cable (-). Never reverse the polarity of the connections. This could cause a fire.
x A highly explosive mixture of gases is given off when the battery is being charged.
x Do not smoke and avoid fires, sparks, and open flames when working. Never create sparks or electrostatic charges when handling cables and electrical equipment. Never short circuit the battery terminals. High-energy sparks can cause serious personal injury.
x Never use or attempt to charge a damaged or frozen battery, or a battery that was frozen but has thawed. Charging a frozen or thawed battery could cause explosions and chemical burns! Replace damaged or frozen vehicle batteries immediately. A dead battery can freeze at temperatures around +32 °F (0 °C).
x If the battery has a vent line or tube, make sure that it is properly connected to the battery.
x Always make sure that the vent line is securely attached to a vehicle battery that is located in the luggage compartment.
WARNING
California Proposition 65 Warning
x Battery posts, terminals, and related accessories contain lead and lead components, chemicals known to the State of California to cause cancer and reproductive harm. Wash your hands after handling.
NOTICE
x Do not expose the vehicle battery to direct sunlight for an extended period of time as ultraviolet rays may damage the battery housing.
x If the vehicle is left standing in the cold for a long time, protect the vehicle battery from freezing. A battery will be permanently damaged by freezing.

Undeployed battery isolator modules are classified as Perchlorate Material. Special handling may apply – see http://www.dtsc.ca.gov/hazardouswaste/perchlorate. Obey all applicable legal requirements regarding handling and disposal of the vehicle or parts of its restraint system, including airbag modules and safety belts with pretensioners. Authorized Volkswagen dealers and authorized Volkswagen Service Facilities are familiar with the requirements, and we recommend that you have them perform this service for you.
Emergency starting and starting the engine with a very weak vehicle battery or after the vehicle battery has been replaced may change or delete settings (including time, date, personal convenience settings and programming). Check the settings and correct as necessary once the vehicle battery has built up a sufficient charge.
Warning light

Checking the vehicle battery electrolyte level

Fig. 185 In the engine compartment: Open the sleeve covering of the vehicle battery.

Fig. 186 In the side of the luggage compartment: On vehicles with 3.6 liter engines, the vehicle battery is on the left side of the luggage compartment.

x First disconnect the negative cable (-) and then the positive cable (+) ⇒ .
Connecting the vehicle battery
x Prior to reconnecting the battery, switch off all electrical systems and devices and the ignition.
x Connect the positive cable (+) first and then the negative cable (-) ⇒ .
After the battery is connected and the ignition is switched on, different indicator lights may come on. They should go out after you drive a short distance at 10–12 mph (15–20 km/h). If the indicator lights do not go out , contact an authorized Volkswagen dealer or an authorized Volkswagen Service Facility and have the vehicle checked.
If the battery was disconnected for a long time, the next scheduled service may not be correctly
calculated and displayed ,Instrument cluster The maximum permissible service and maintenance
intervals are shown in the ⇒ booklet Warranty and Maintenance.
Vehicles with Keyless Access
If the ignition will not start after reconnecting the vehicle battery, lock the vehicle from the outside and unlock it again, Unlocking and locking vehicles with Keyless Access. Then try to start the ignition again. If the ignition cannot be switched on, contact an authorized Volkswagen dealer, an authorized Volkswagen Service Facility, or another qualified workshop for assistance.
Automatic electrical load deactivation
If the vehicle battery drain is high, the intelligent onboard electrical system management automatically takes steps to help prevent battery drain.
x The idle speed is increased so that the alternator provides more power.
x The power to devices that consume a lot of electricity is cut back or switched off completely.
x When the engine is started, the power supply to the 12 Volt sockets and the cigarette lighter, Cigarette lighter is temporarily interrupted.
The onboard electrical system management cannot always keep the battery from being drained. For example, the battery will drain if the engine is not running, but the ignition is switched on or the parking lights are left on for a long time when parked.
Battery disconnection in an accident with airbag deployment
In vehicles with a battery in the luggage compartment, the electrical connection to the battery is disconnected automatically in a collision with airbag deployment. This helps to prevent a short-circuit.
What drains the vehicle battery?
x Long periods when the engine is not running, especially when the ignition is on.
x Using electrical systems or devices when the engine is switched off.
x Leaving the vehicle unlocked for several days when not in use.
x The selector lever is left for a long period of time in any position other than P when the ignition is switched off, Automatic transmission: Selector lever.
WARNING
Failure to use the proper battery with proper mounting and connections may cause short circuits, fires, and serious personal injuries.
x Always use only maintenance-free or cycle-free, leak-proof batteries with the same specifications and dimensions as the original equipment battery. Specifications are listed on the battery housing.

WARNING
When the vehicle battery is charged, it produces highly explosive hydrogen gas.
x Charge vehicle batteries only in well-ventilated areas.
x Never charge a frozen or thawed battery. A dead battery can freeze at temperatures around +32 °F (0 °C).
x You must replace the vehicle battery if it was frozen.
x Incorrectly connected cables can cause a short-circuit. First connect the positive cable (+) and then the negative cable (-).
NOTICE
x Never disconnect a vehicle battery or connect 2 vehicle batteries to each other when the ignition is switched on or the engine is running. Using the wrong battery can damage the electrical system or electronic components and cause electrical malfunctions.
x Never use a vehicle battery that does not meet specifications for the vehicle battery for your vehicle . Using the wrong battery can damage the electrical system or electronic components and cause electrical malfunctions.
x Never connect power generating equipment, such as a solar panel or battery charger, to the 12 Volt socket or the cigarette lighter, Cigarette lighter in order to charge the vehicle battery. This can damage the vehicle's electrical system.
Dispose of the vehicle battery according to regulations. Vehicle batteries contain poisonous substances such as sulfuric acid and lead.
Battery acid can pollute the environment. Catch leaking operating fluids and dispose of them properly.