27th Mar 2015, 19:59
The heater blower only goes on four, means that the relay switch is gone on your car. It's under the blower motor on the passenger side of your car (VW Polo 1.4). It only takes few seconds to fix; two screws on it, clip the connection away and replace the old with a new one.
John.
8th Jan 2013, 16:42
Usually the heating fan has a resistor package that controls the different ventilation speeds. If level 4 is the only one that works, then the chances are high that the resistor package must be replaced.