Mercedes-Benz GLK-Class 2015 Owners Manual - Manual (Page 326)

R Only use jumper cables which have a sufficient cross-section and insulated terminal clamps.
R If the battery is fully discharged, leave the battery that is being used to jump-start connected
for a few minutes before attempting to start. This charges the battery slightly.
R
Make sure that the two vehicles do not touch.
Make sure that:
R the jumper cables are not damaged.
R bare parts of the terminal clamp do not come into contact with other metal parts while the
jumper cables are connected to the battery.
R
the jumper cables cannot come into contact with parts such as the V-belt pulley or the fan.
These parts move when the engine is started and while it is running.
X Apply the parking brake firmly.
X Shift the automatic transmission to position P.
X
Switch off all electrical consumers, e.g. rear window defroster, lighting, etc.
X
Open the hood.
Position number B identifies the charged battery of the other vehicle or an equivalent jump-
starting device.
X
Slide cover : of positive terminal ; in the direction of the arrow.
X
Connect positive terminal ; on your vehicle to positive terminal = of donor battery B
using the jumper cable, beginning with your own battery.
X
Start the engine of the donor vehicle and run it at idling speed.
X
Connect negative terminal ? of donor battery B to ground point A of your vehicle using
the jumper cable, connecting the jumper cable to battery of other vehicle B first.
X Start the engine.
X Before disconnecting the jumper cables, let the engine run for several minutes.
324
Jump-starting
Breakdown
assistance