BMW 5 Series: Cold-start phase
Point A in the heat management module circuit diagram designates the cold start with an engine that has completely cooled down.
Cold-start phase, Bx8TU engine
In the cold-start phase, the coolant circulates exclusively via a bypass in the coolant pump. The rotary valve in the heat management module closes the coolant lines so that the excess pressure that builds up opens the pressure relief valve in the coolant pump (opening pressure 2.1 bar) and the coolant is recirculated in the coolant pump.
Because the coolant circuits through the exhaust turbocharger and the ventilation line of the cylinder head cannot be closed, a low volumetric flow is returned to the coolant pump here.
Warm-up phase
Area B in the circuit diagram for the heat management module shows the opening angle of the rotary valve in the warm-up phase.
Warm-up phase, Bx8TU engine
In the warm-up phase, the heat management module additionally opens the connection to the heating in addition to opening the bypass line. The coolant flows through the cylinder head, the exhaust turbocharger and the engine oil/coolant heat exchanger. The electric split cooling valve is closed; no coolant flows through the engine block (split cooling).
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Operating temperature
The positions of the rotary valve at engine operating temperature are shown
by area C of the circuit
diagram.
Operating temperature, Bx8TU engine
The graphic shows control with the engine at operat
Coolant pump
The layout and function of the coolant pump have been revised and adapted to
match the cooling
concept of the Bx8 TU engines.
Coolant pump, Bx8TU engine
Pressure relief valve closed (pr
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Warning and braking function
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Vehicle symbol lights up red
Increase distance and brake if necessary
Acute warning:
Vehicle symbol flashes red and a signal
sounds
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evasive action, if required
Acute warning:
Person symbol flashes red and a s
Calls with multiple parties
General information
You can switch between calls or connect two
calls to a single conference call. These functions
must be supported by the mobile phone and
service provider.
Accepting a call while speaking to
another party
If a second call comes in during an ongoing call,
a call waiting signal soun
