General advice on working with EMS
The following advice must be followed to avoid
damage to the engine control unit and other elec-
The system must be disconnected from system volt-
age (by cutting the current with the main switch) and
the starter key(s) must be in the 0 position when the
engine control unit connectors are disconnected or
the current with the main switches
when an engine is running.
Never undo a battery cable when the engine is run-
Turn the main switches off or disconnect the battery
cables during quick charging of the batteries.
NOTICE! During normal trickle charging, it is not
necessary to turn the main switches off.
Only batteries may be used for start help. A help
start device can produce a very high voltage and
damage the control unit and other electronics.
If a connector is disconnected from a sensor, be
very careful to avoid allowing the contact pins to
come into contact with oil, water or dirt.
1 NOTICE! Cut the current with the main switch.
The system must be disconnected from system
voltage when the engine control unit connectors are
disconnected or connected.
2 Undo the two connectors from the engine control
unit before any electrical welding starts. Turn the
locking arm down at the same time as the connector
is pulled outwards.
3 Disconnect all connections to the alternator.
Connect the welder earth clamp to the component
to be welded, or as close as possible to the weld
site. The clamp must never be connected to the
engine or in such a way that current can pass
through a bearing.
After welding is completed, the disconnected com-
ponents, such as alternator cables and battery
cables must be connected in the correct order.
The battery cables must always be connected last.
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