thought I'd update this as it might help someone else.
The pre 2015 halogen (not HID) V40 has two 501's in each headlight that make up the 'position light'
One is orange and one is white
Due to the way its wired, Both orange and white bulbs have to blow for the car to give a warning about 'position light malfunction'.
(Not the best design)
It turns out both Right and Left white 501's had blown on my car, plus the orange 501 on the drivers side. So I was only getting one error on the divers side where both bulbs had blown.
The newer halogen (not HID) V40's dont have the orange bulb anymore. Just white.