294 If and when
Jump leads
Jump leads must comply with standard DIN 72553 (see manufacturer's doc-
umentation). The wire cross section must be at least 25 mm2 for petrol en-
gines and at least 35 mm2 for diesel engines.
Note
●The vehicles must not touch each other, otherwise electricity could flow
as soon as the positive terminals are connected.
●The discharged battery must be properly connected to the vehicle elec-
trical system.
How to jump start: description
Fig. 244 Diagram of con-
nections for vehicles
without Start-Stop sys-
tem
Fig. 245 Diagram of con-
nections for vehicles
with Start-Stop system
Jump lead terminal connections
1. Switch off the ignition of both vehicles ⇒ .
2. For vehicles without Start-Stop system:
–Connect one end of the red jump lead to the positive + termi-
nal of the vehicle with the flat battery A ⇒ Fig. 244.
–Connect the other end of the red jump lead to the positive ter-
minal + in the vehicle providing assistance B.
–Connect one end of the black jump lead to the negative terminal
– of the vehicle providing assistance B ⇒ Fig. 244.
–Connect the other end of the black jump lead X to a solid met-
al component bolted to the engine block or to the engine block
itself of the vehicle with the flat battery. However, connect it to
a point as far as possible from the battery A.
3. For vehicles with Start-Stop system:
