Volvo S90 2019 Owner's Manual page 476

STARTING AND DRIVING
Overloading the starter battery
The electrical functions in the car load the
starter battery to varying degrees. Avoid
using the ignition position II when the car is
switched off. Instead, use ignition position I -
which uses less power.
Also, be aware of different accessories that
load the electrical system. Do not use func-
tions which use a lot of power when the car is
switched off. Examples of such functions are:
ventilation fan
•
headlamps
•
windscreen wiper
•
audio system (high volume).
•
If the starter battery voltage is low, a message
is shown in the driver display. The energy-sav-
ing function then shuts down certain functions
or reduces certain functions such as the venti-
lation fan and/or audio system.
In which case, charge the starter battery
–
by starting the car and then running it for
at least 15 minutes - starter battery charg-
ing is more effective during driving than
running the engine at idling speed while
stationary.
Related information
Starter battery (p. 608)
•
Ignition positions (p. 424)
•
474
Using jump starting with another
battery
If the starter battery is discharged then the
car can be started with current from another
battery.
Attachment points for the jump leads. The appear-
ance in the engine compartment may vary depending
on car model and equipment level.
When jump starting the car, the following
steps are recommended to avoid short circuits
or other damage:
1. Set the car's electrical system in ignition
position 0.
2. Check that the donor battery has a voltage
of 12 V.
3. If the donor battery is installed in another
car - switch off the donor car's engine and
make sure that the two cars do not touch
each other.
4. Connect one of the red jump lead's
clamps to the donor battery's positive ter-
minal (1).
IMPORTANT
Connect the start cable carefully to avoid
short circuits with other components in the
engine compartment.
5. Open the positive jump-starting point's
cover (2).
6. Connect the red jump lead's other clamp
onto the car's positive jump-starting point
(2).
7. Connect one of the black jump lead's
clamps to the donor battery's negative ter-
minal (3).
8. Connect the black jump lead's other
clamp onto the car's negative jump-star-
ting point (4).
9. Check that the jump lead clamps are
affixed securely so that there are no sparks
during the starting attempt.