The discharged vehicle battery must be properly connected to the vehicle's electrical system.
The vehicles must not touch. Otherwise electricity could flow as soon as the positive terminals are
connected.
Ensure that the battery clamps have good metal-to-metal contact with the battery terminals.
If the engine does not start immediately, switch off the starter after about 10 seconds and try again
after about half a minute.
The steps should only be carried out in the specified order.
Attaching the jump leads
•Switch off the ignition in both vehicles ⇒ Starting and stopping the engine.
•If necessary, open the battery cover in the engine compartment ⇒ Vehicle battery.
•Connect one end of the red jump lead to the positive terminal ⇒ Fig. 171⊕ or ⇒ Fig. 172⊕ in
the vehicle with the discharged battery Ⓐ ⇒.
•Connect the other end of the red jump lead to the positive terminal ⊕ in the vehicle providing
assistance Ⓑ.
•In vehicles without start/stop system: connect one end of the black jump lead to the negative
terminal ㊀ in the vehicle providing assistance Ⓑ ⇒ Fig. 171.
•In vehicles with start/stop system: connect one end of the black jump lead Ⓧ to a suitable
earth connection, to a solid metal part that is securely bolted onto the cylinder or to the cylinder
block itself ⇒ Fig. 172.
•Connect the other end of the black jump lead Ⓧ to a solid metal component bolted on to the
engine block, or onto the engine block in the vehicle with the discharged battery. Do not
connect it to a point near the battery Ⓐ ⇒.
•Position the leads in such a way that they cannot come into contact with any moving parts in the
engine compartment.
Starting the engine
•Start the engine of the vehicle providing assistance and let it run at idle.
•Start the engine of the car with the discharged vehicle battery and wait two or three minutes
until the engine is running smoothly.
Removing the jump leads
•Before disconnecting the jump leads, switch off the dipped beam headlights if they are switched
on.
•Turn on the heater blower and rear window heater in the vehicle battery with the discharged
battery. This helps minimise the voltage peaks generated when the leads are disconnected.
•With the engines running, disconnect the jump leads in the exact reverse order to the
instructions given above.
•Close the battery cover.
Tow-starting and towing
Introduction
This chapter contains information on the followingsubjects:
⇒ Notes on tow-starting
⇒ Notes on towing
Jump starting the vehicle incorrectly can cause the battery to explode, which can lead to
serious injuries. Please note the following in order to reduce the risk of the battery exploding:
•All work on the vehicle battery and the electrical system can cause serious chemical
burns, fire and electric shocks. Always read the warnings and safety information before
carrying out any kind of work on the vehicle battery ⇒ Vehicle battery.
•Always wear suitable eye protection and never lean over the vehicle battery.
•Attach the connector cables in the correct order – the positive cable first, followed by the
negative.
•Never connect the negative cable to parts of the fuel system or to the brake lines.
•The non-insulated parts of the battery clamps must not be allowed to touch. The jump lead
attached to the positive vehicle battery terminal must not touch metal parts of the vehicle.
•Check the window on the vehicle battery using a torch if necessary. If the display is light
yellow or colourless, do not jump start the vehicle. Seek expert assistance.
•Avoid electrostatic discharge in the vicinity of the vehicle battery. The gas emitted from the
vehicle battery could be ignited by sparks.
•Do not use jump leads to start the engine if the vehicle battery is damaged or if it is or has
ever been frozen.
WARNING
