
Switch, coolant level
The switch is located in the expansion tank.
It’s
purpose
is to detect if the coolant level in the cooling
system (expansion tank) becomes too low. The switch
is a magnetically sensitive switch. A float located
around the switch affects the switch differently depend-
ing on the coolant level. A alarm signal is sent when
the coolant level is too low.
Cold start valve
In order to avoid boiling in the charge air coolers at
different loads and coolant temperatures, the system
is fitted with a cold start valve that is controlled by the
EMS2. The cold start valve is normally open i.e. without
voltage supply the valve is open.
Preheat relay
In cold climate the intake air might need to be pre-
heated. This is done by the preheater located on the
intake manifold. The preheater is controlled by the
EMS2 via the pre-heat relay.
30-0 General
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