Hello and Welcome..
My name is MIKE - Im happy to help / advise you ..
I note you say that the water is leaking in beneath
the light clusters... but of course it could be coming in anywhere above that - and running down.. you would need to be sure of that -
Common faults causing water leaks in the boot area in this model are the rubbers around the tailgate hinges... also - the rubber seal - around the boot / tailgate aperture -
Too - on models equipped with a rear wash system, its a common fault for the water nozzle supply pipe to leak - water comes into the tailgate - runs down and out - and around the lights - so thats to be considered also.
If all else as above is ruled out, then you must still have a place on the rear light unit thats letting water in... It can be very difficult - If sealing with silicone -copious
amounts are usually needed so that it pushes into even the slightest area where they may be leaking.. You may have to remove them and real. In fact doing so - you would see then where your original seal has sealed - and not sealed giving you a clue there..
There was a Ford Tsb on this issue - Ive referred to it above - re the seals.. I will give you this below :
So working through as above you should get this cured - Let me know how you get on..Do let me know if you need anything else at all -
Kind Rgds - MIKE.
..............Please do click on the "OK/ Excellent ratings"
for me as that's how Im credited for helping you - Thank you in advance for that
You can and are most welcome to get back to me anytime you might need - clicking the OK ratings does not close you out at all..