well I took it for a roadworthy and they said it was 'faulty' so i'm not entirely sure, I'm not that knowledgable about cars yet (learning as I go mostly) so if you could show me where it is in the car / what it is i'll have a go at cleaning it. The place i took the supra to to get roadworthied said the engine was leaking oil aswell but it doesn't, it's just really dirty, so it could be the same thing with this switch.