I had the same problem some time ago. No dismantling needed. You need to go on the passanger's side, under dashboard, behind glovebox, center right. You'll be able to see a set of wires connected upwards (coming from the fan motor). That's the fan speed control card the wires are connected into. You can only see a couple of screws, one on each side. Unscrew and pull out. Replace and that's it.
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