Polo 9n3 1.2 - Radiator fan not working

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Drives: Polo 9N2 1.2
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Polo 9n3 1.2 - Radiator fan not working

Post by Amos91 »

Hi all,

Hope someone can give me some pointers on this! The Polo in question was running completely find before I started messing around with it! The issue being the radiator fan switch was weeping coolant so got a HAAS fan switch to replace.

All went well at first and I'm certain that the radiator fan kicked in once the car got hot, but did not spin when the AC was switched on?

However I noticed that even the new switch was weeping coolant, so popped it off again and decided to clean up the facing as much as possible, this time all good and no more leak.

The issue is now that the radiator fan doesn't seem to be engaging at all and if left to idle after a run will start to see the coolant temp rise above 90°C, which it never used to do.

What I have done -

1) Unplugged the radiator fan switch and can see there is a live 12V feed here. When bridging this 12V feed with one of the other pins I can hear a relay click but no fan. When bridging the remaining pin with the 12V feed nothing happens with the car on or off (I assume this is the high speed setting).

Could anyone point me toward the next steps?

• Try and manually feed the radiator fan to see if it powers on? Does anyone have the wiring for that plug? +/-
• Replace the fan control module - do these Polo's have one and if so where is it located?

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Re: Polo 9n3 1.2 - Radiator fan not working

Post by RUM4MO »

Hi, Google VW radiator fans not running and that should head you to something that includes a wiring diagram all these VW Group cars are roughly the same in terms of fan(s) or fan speeds control.

From memory there could be 2 separate fuses and you might have blown one of them when fitting that link to test the two fans or two fan speeds.
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Re: Polo 9n3 1.2 - Radiator fan not working

Post by CarbonChaos »

Polos do have a habit of broken wires for the fan/ switch at the front of the gearbox area, check these carefully around the plastic securing clip/ bracket.

Let us know how it goes.
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