Radiator Cooling fans

[Gregg1100]

Can anyone Tell me which is the main fan- the one that kicks in first, please ?. The one on battery end, or the HP pump end.
Thanks

[VertVega]

I guess the car is Xantia.
Both fans work together and they can be off, low speed or high speed.

When the air condition is switched on they both spin in low speed (with normal coolant temperature).

Edit: If you have only one fan functioning then it means that the other fan brushes are gone.
The single fan kicks in when the coolant temperature has gone over the "Too Hot" threshold level and it runs in high speed.
That's because of the switching between serial / paralel modes (3 relays).

[VertVega]

I added a topic in Handy Hints & Tips. It might help you if you have to replace the fan motor.
---> Xantia II - Radiator fan motor removal

[MikeT]

Edit: If you have only one fan functioning then it means that the other fan brushes are gone.
The single fan kicks in when the coolant temperature has gone over the "Too Hot" threshold level and it runs in high speed.
That's because of the switching between serial / paralel modes (3 relays).

It's been a while but I'm fairly sure only one fan running can be due to other faults too and is a clear sign something's wrong. It's such a common fault, many owners are lead to believe single fan running is normal, it's not.

Without faults, both fans should always run together, whether low or high speed.

Typical faults are failed wiring and failed relays.

[Clogzz]

http://www.frenchcarforum.co.uk/forum/v ... hp?t=31403" onclick="window.open(this.href);return false;

[Gregg1100]

It seems that the one nearest battery is seizing up. Air conditioning is on the car, but I have never bothered with it- not hot enough in this country for more than two days on the trot mess about with with.

[VertVega]

"seizing-up" is actually due the weakened contact surface of the brushes / shortened length (check last pic. in my above link).

Clogzz has sent the electrical drawings where the relays and the radiator fans are seen.
In low speed they are connected in series. One motor is cutting the continuity of the current flow.
So your both fans might work (in high speed) when the coolant temperature rises to very hot level (cold -> hot -> very hot). But if it has been for a long time then the second motor will never turn.

To save extra gasket change work you should replace that motor causing problems.
I guess it starts turning if you hit gently with a screw driver or give a little help by rotating from the blades.

[Clogzz]

To test the fans, you switch the air conditioning on to start both fans at the low speed.
They must then spin irrespective of whether the aircon works or not.

[Carsten S]

To test the fans, you switch the air conditioning on to start both fans at the low speed.
They must then spin irrespective of whether the aircon works or not.

Are you sure? If I remember correct, the pressure-guard switch off the AC compressor and the fans, if the pressure in the AC-lines are to low (empty)

[Clogzz]

Are you sure?

Yesse, certainly on the Mk I.
I disconnected the pressure switch and the fans still came on.
The fans come on less than one second after switching on the AC, while the compressor only clutches in after the pressure switch says that it's OK to do so.

[taffy]

mine havent worked since ive had the car i have to use the inside heater fan to keep it ok...air con pump seized and fans...will have to get round to it soon suns out lol!!

[Gregg1100]

Car is S2 1.9 TD-