Vehicles with 4-cyl. engine and heater coolant shut-off valve N279 — AUDI

Vehicles with 4-cyl. engine and
heater coolant shut-off valve
N279
Note
Vehicles with 4-cyl. engine are not provided with a
heater coolant shut-off valve
N279
at present. Vehicles manufactured up to Model Year 2005 may be fitted with a shut-off valve, but this is not actuated (the
auxiliary heater control unit
J364
must be encoded accordingly)
Chapter
(Encoding auxiliary heater).
At the start of production (up to Model Year 2004), vehicles with 4-cyl. engine were fitted with the
heater coolant shut-off valve
N279
. However, in view of the fact that cold starting problems may be encountered with these engines at very low ambient temperatures following auxiliary heating operation with a small coolant circuit (engine is only slightly pre-heated), the
auxiliary heater control unit
J364
is to be encoded such that the
heater coolant shut-off valve
N279
is not actuated.
For all components not mentioned, refer to
Cooling
Rep. Gr.
19
Engine, mechanics
Depending on the engine version, the tubing from the engine to the auxiliary heater/from the heat exchanger to the engine may differ from this illustration
Cooling
Rep. Gr.
19
Engine, mechanics
The direction of coolant flow is regulated in auxiliary heating mode as a function of coolant temperature and the setting in the
control unit in dash panel insert
J285
by the
auxiliary heater control unit
J364
Chapter
.
Direction of coolant flow (temperature-dependent, refer to note)
“⇒”
In auxiliary heating mode and with
heater coolant shut-off valve
N279
actuated (shut-off valve actuation is not provided at present).
“→”
In auxiliary heating mode and with shut-off valve not actuated, also with engine running (and shut-off valve not actuated).
1
Auxiliary heater
2
Circulation pump
V55
Under certain conditions, the circulation pump is also actuated with the engine running to assist the engine coolant pump
Chapter
3
Heater coolant shut-off valve
N279
Removing and installing
Chapter
The shut-off valve is actuated by the
auxiliary heater control unit
J364
Note
Vehicles with 4-cyl. engine are not provided with a
heater coolant shut-off valve
N279
at present. Vehicles manufactured up to Model Year 2005 may be fitted with a shut-off valve, but this is not actuated (the
auxiliary heater control unit
J364
must be encoded accordingly)
Chapter
(Encoding auxiliary heater).
At the start of production (up to Model Year 2004), vehicles with 4-cyl. engine were fitted with the
heater coolant shut-off valve
N279
. However, in view of the fact that cold starting problems may be encountered with these engines at very low ambient temperatures following auxiliary heating operation with a small coolant circuit (engine is only slightly pre-heated), the
auxiliary heater control unit
J364
is to be encoded such that the
heater coolant shut-off valve
N279
is not actuated.
At the factory, the
auxiliary heater control unit
J364
is encoded for a vehicle with no
heater coolant shut-off valve
N279
. The
heater coolant shut-off valve
N279
is thus not actuated
Chapter
(Encoding control unit).
4
Heat exchanger of heater or air conditioner unit
5
Engine