BMW 5 Series: 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 (pressure < 2.1 bar)
- Pressure relief valve opened (pressure > 2.1 bar)
A pressure relief valve is installed in the mechanical coolant pump housing.
In combination with the
heat management module, the pressure relief valve on the one hand ensures that
the engine operating
temperature is reached more quickly, while at the same time reducing leaks and
component damage
due to high pressure in the cooling system.
If an excess pressure of more than 2.1 bar builds up in the coolant circuits,
the pressure relief valve
opens and releases a bypass channel. The coolant is now exclusively circulated
in the pump body.
Once the pressure drops below 2.1 bar or the engine speed rises above 3000 rpm,
the pressure relief
valve closes and the coolant is again routed through the engine's coolant ducts.
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On-board diagnosis
Feed-in point of the blow-by gases to the clean air line upstream from the
exhaust turbocharger
Non-return valve
Connection to exhaust turbocharger
Captive screws
Crankcase
B58TU exhaust turbocharger
Exhaust turbocharger in the B58TU engine
Exhaust turbocharger made of steel, for cylinder head-integrated exhaust
manifold ZIAK¹
Exhaust turbocharger made of steel, f
SEE MORE:
General information
The system cannot be activated or meaningfully
used in certain situations.
Safety information
Warning
The system is designed to operate in certain
conditions and circumstances. Due to conditions
or other factors, the system may not respond.
There may be a risk of accident or ris
The Lane Departure Warning is an element of the Active Driving Assistant,
optional equipment (OE
5AS) and the Active Driving Assistant Plus, optional equipment (OE 5AT).
The Lane Departure Warning detects lane markings from a speed of approximately
43 mph (70 km/h)
and warns the driver again