Volvo V70 Owner's Manual page 101

Jumpstarting with a booster battery is as follows:
If for some reason the battery in your car is discharged, you can "borrow"
current from a spare battery or another car's battery to start the engine.
Always check that the clamps are secure so that there are no sparks during
the start attempt.
To avoid the risk of explosion, we recommend you do exactly as follows.
·
Turn the ignition key to position 0.
·
Ensure that the booster battery has 12 volt current.
·
If the booster battery is in another car, stop the engine of that car and
make sure the cars are not touching.
·
Connect the red cable to the booster battery's positive terminal (1+)
and the red connection in your car's engine by (2+).
The clamp should be attached to the contact point located under a little
black cover with a plus sign on it. The cover is connected to the cover
of the fuse box.
9 8
Jumpstarting
Lifting eye - diesel
engine (under bonnet on
right in engine bay)
3100088m
·
Connect one end of the black cable to the booster battery's negative
terminal (3).
·
Connect the other end of the black cable to the lifting eyes on you car.
No. 4 in the illustration.
·
Start the engine of the "booster car". Let the engine run a few minutes
at a speed slightly higher than idle, 1500 rpm.
·
Start the engine of the car with the discharged battery.
·
NOTE! Do not move the clamps during the start attempt (risk
of spark buildup).
·
Remove the clamps in reverse order.
WARNING!
Remember that batteries, especially the
booster battery, contain oxyhydrogen
which is highly explosive. A spark, which
can be caused if you incorrectly install the
jump leads, is enough to cause the battery
to explode and both damage the car and
injure you. The battery also contains
sulphuric acid, which can cause serious
corrosive damage. If the acid comes into
contact with your eyes, skin or clothes,
flush with large quantities of water. If acid
splashes into your eyes contact a doctor
immediately.