BMW 3: Coolant pump
The layout and function of the coolant pump have been revised and adapted to
match the cooling
concept of the B46TU/B48TU engines.

Coolant pump
- Pressure relief valve closed (pressure < 2.2 bar / 32 psi)
- Pressure relief valve opened (pressure > 2.2 bar / 32 psi)
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 2.2 bar (32 psi) builds up in the coolant
circuit, 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 2.2 bar (32 psi), the pressure relief valve
closes and the coolant
is again routed through the coolant ducts.
READ NEXT:
Exhaust turbocharger
Exhaust turbocharger
The exhaust turbocharger can be replaced individually and is exclusively made
of steel. The boost
charge pressure is still controlled by an electrical waste
The fuel system is made up of the fuel supply and fuel preparation systems.
The fuel supply includes
the fuel tank with all mounted parts and the fuel lines up to the engine
compartment.
The fuel p
The fuel preparation has again been adapted to meet the emission legislation
requirements. The high
pressure pump and the injectors have been revised and designed for an fuel
injection pressure of
3
SEE MORE:
Concept
The rearview camera provides assistance in
parking and maneuvering backwards. The area
behind the vehicle is shown on the Control Display.
Safety information
Warning
The system cannot serve as a substitute for the
driver's personal judgment in assessing the
traffic conditions. There is a ri
Concept
Contact the BMW Group Roadside Assistance if
assistance is needed in the event of a breakdown.
General information
In the event of a breakdown, data on the vehicle's
condition is transmitted to the BMW Roadside
Assistance.
There are various ways of contacting BMW
Roadside Assistance.
Via