Bin tinkering with my fascia, resprayed, connected the wiring for fogs, heater and hazards and the light furthest to the right won't come on when pressed. Heaters blowing so am I right in assuming it's a bulb in the switch. I didnt disconnect the battery as I installed a new stereo and took me awhile to sort grounding to chassis so I thought I'd not disconnect battery again. Everything lights up, just not the end one for heater.. Any ideas?