2015 VOLKSWAGEN PASSAT engine

Engine coolant

Warning light and engine coolant temperature gauge

Fig. 184 Engine coolant temperature gauge in the instrument cluster: A Engine cold; B Normal temperature range; C Warning zone.

Lights up
Temperature gauge needle
⇒ fig. 184
Possible cause Proper response
(B) Normal range Engine coolant level too low.
Check the engine coolant level after the engine has cooled down and add engine coolant if low. If the engine coolant level is correct or the problem continues after adding coolant, do not drive any farther. Contact an author-ized Volkswagen dealer or authorized Volkswagen Service Facility. These instructions apply only when the coolant temperature stays in the normal range. Stop immediately if the needle goes into the red warning zone (C).
– Engine coolant system malfunction.

Engine coolant specifications

Checking engine coolant level and topping off

Fig. 186 Coolant expansion tank in the engine compartment.

Fig. 187 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 specifica-
tions ) ⇒ .
x The engine coolant level must be inside the marks on the side of the reservoir ⇒ fig. 186. 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 (⇒ 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 com-ponents 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 ⇒  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 author-ized 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 ⇒ fig. 186. 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 sys-tem. Have the engine cooling system checked immediately by an authorized Volkswagen deal-er 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.

More information:
x ⇒ Booklet Warranty and Maintenance
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. Recon-nect 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 ultra-violet rays may damage the battery housing.