Volvo VNL 780 Operator's Manual page 464

454 MAINTENANCE AND LUBRICATION
CAUTION
Attempting to work on electronic
components without proper equipment
can damage internal parts with static
electricity.
CAUTION
Today's vehicles contain a high number
of electronic devices. It is very important
to exercise caution when working on
a modern electrical system, charging
batteries or jump starting the engine.
To minimize the risk of any damage to
the electronic components, follow the
procedures below when work is being
done to the electrical system.
CAUTION
Welding on the vehicle can damage the
electrical system or components due
to the high voltage and current spikes
that normally occur when welding. It
is preferable to avoid welding on an
assembled vehicle. However, if any
structure on or in contact with the
vehicle must be welded, follow the
recommendations below.
CAUTION
If there are other ground cables connected
to the battery (such as engine ECU,
transmission ECU, etc.), disconnect those
wires first, then remove the main battery
ground cable. Electronic modules may
be damaged when their ground(s) are
connected/disconnected with the main
battery ground disconnected. Therefore,
disconnect the main battery ground last or
when installing, connect the main ground
first.