I have changed the bulb today in the switch for the drivers heated seat. However as previously when on low the light comes on but when on high the light does not come on. The bulb was changed by removing the blue centre plastic circle. I tried removing the brown ones on either side but the don't pop out and I'm wondering if the brown for the high setting needs changing, but not sure what's behind the brown? A bulb or a resistor. Or does my problem lie elsewhere?