air conditioning AUDI S4 1998 B5 / 1.G Engine Manual

12
Electric circuit of fan control:
Engine
for vehicles with air-conditioning system:
Integrated in the pressure switch for air
conditioner F129 is the high-pressure switch
for activating a higher fan setting.
The pressure switch is mounted below the
right-hand headlight behind the bumper.
Components:
F18/F54 Radiator fan thermoswitch
F95 Thermoswitch for continued coolant
function
F129 Pressure switch for air conditioner
(only for vehicles with air conditioner)
V293 Control unit for radiator fan
V7 Radiator fan (induced-air fan)
V51 Continued coolant circulation pump
V177 Fan 2 for radiator (forced-air fan)
(only for vehicles with air conditioner)
1 Terminal 30, positive supply via fuse
on 8-socket relay plate
2 Terminal 61, D+ (alternator) via fuse on
8-way relay
3 Fan activation (only for vehicles with
air conditioner)
M_
V293 F18
F54
F129
V177V7 V51
M_
M_
SSP 198/17
*
*
F95
*
P
P
123

only for vehicles with air conditioner
Air-conditioning pressure switch F129

13
Function of fan circuit
(for vehicles with air-conditioning
system)
4 fan settings are possible:
is activated by coolant pump thermoswitch
F95.
The fan motors and continued coolant
circulation pump V51 are activated.
The fan motors run at min. output (40%).
is requested by radiator fan thermoswitch F18
or by the air-conditioning control panel.
The fan motors run at 50% output.
is activated by air-conditioning system
pressure switch F129.
The fan motors run at 85 % output.
is activated by radiator fan thermoswitch F54.
The fan motors run at full output.
Fan speeds 1, 2 and 3 are only
activated if the “engine running“
signal is picked up at terminal 61.
The electrical coolant function.....
The continued coolant function is
only activated if the “engine not
running“ signal is picked up at
terminal 61. The continued coolant
function period is limited to 10
minutes.
Fan speed 1......
Fan speed 2......
Fan speed 3......