What product/method have you used with good long-term results? Been working on sprucing up the exterior of my 3rd gen, but haven't found anything that works on the trim around the doors and windows:
it looks like yours sits outside a lot and is in a humid climate. looks like mold is growing on there. try some bleach and wipe it down. that should kill all the spores.
I have used Mothers Back to Black on plastic moldings and rubber seals, not sure it would do anything for your application but for $5 - $6 it might be worth a try?