My Octavia II heater fan was only working on position 4.
Whipped out the ballast resistor and sure enough the thermal fuse had blown.

Changed the thermal fuse (no need to replace the ballast resistor unless damaged just don't solder the new one on - think about it)

Fuses only cost a couple of quid instead of around £15 for an after market ballast unit (and about £35 for a genuine one)

Fuse blew again pretty quickly so I took the fan out. It seemed only a little sticky in the bearings so I cleaned it and put it back.

Also replaced the pollen filter which was pretty mucky.

Bugger! Fuse blew again.

So, bit the bullet and fitted a new fan (after market - £70)

Success!!

Everything is easily accessible under the glove box (RHD model)

Conclusion; Even a slightly stiff fan will not start on position one or two as the ballast is sopping up most of the current. Ballast overheats and blows the fuse.

Unfortunately there doesn't seem to be a way to replace the bearings on the fan motor.

Won't stop me trying though.

Could you not get access to the bearings to try some oil ?

Update;

Now the system is not working on ANY speed.

Ballast blown again.

This is getting beyond me, there must be other control/relay/something that i don't know about.

Or just a bad connection somewhere.

One for the experts I'm afraid.

Meanwhile, wired the fan direct to battery via a switch so I have a blower which is a bit essential in this weather.

Edited 9 December, 20178 yr by PeteF
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