Asking for a friend who has just found out that both tail lights are suddenly not working on her 51 plate Fiesta. Thinking it could be the fuse I tried to look up online to see where the tail light fuse it and I'm completely baffled - I can find all the fuses but this one! Anyone have any idea? Grateful for any help. 

Could just be bulbs?

Unsure whether '51 plate will be a late Mk5 or early Mk6?  The Mk5's had no end of earth faults with the tail lights.

3 minutes ago, TomsFocus said:

Unsure whether '51 plate will be a late Mk5 or early Mk6?  The Mk5's had no end of earth faults with the tail lights.

Thanks - I think it is a Mk5 but will check. Is the earth fault a simple fix? I'm still mystified that the fuse isn't shown anywhere. 

7 minutes ago, Findlay said:

Thanks - I think it is a Mk5 but will check. Is the earth fault a simple fix? I'm still mystified that the fuse isn't shown anywhere. 

Sidelights take such a small amount of power they don't really need to be fused separately.  If they are fused it'll only be a small 5 amp fuse.  Fuseboxes are different between Mk5 and Mk6 though so I would need that confirmed before I spend any time checking those.

Earth faults are usually easy to fix, just a rusty light board or a corroded plug.  You can check for these by trying other lights at the same time, if you find the sidelights come on with brake lights or flash with indicators then that is a sure sign of an earth fault for example.

According to Haynes, P12.37, there are two Fuses, F6 and F7, two different earth points.  The two number plate lights and front side lights are fed from the same two circuits.

Similar to P12.27, pre 2000.

In my (limited) experience, left and right lights generally are fed from different fuses.

2002 onwards slightly different, number plate lights are on a seperate fuse.

Thanks for your help guys, I'll relay these messages. 

1 hour ago, Findlay said:

Thanks for your help guys, I'll relay these messages. 

As said previously, check the bulbs first!