Disco 2 FUSES OR BCU ???

2001 DII TD5

Hi all - got a few "electrical" issues and wonder if problem is more likely to be fuse box or BCU related

Thing got drenched in torrential rain last week, and has always leaked via head lining/offside front pillar, so could well have had some moisture down to the fusebox area

first thing that went wrong was that the alarm went off - so changed the key fob battery, but now symptoms are:

no indicators (it's like driving a BMW or Merc !)
no intermittent wiper control (other speeds are ok)
no central locking (via fob or instrument panel switch); all doors now deadlocked other than drivers door;
no chimes when door open and lights on (sometimes !)

local garage has hooked the thing up to diagnostics, and shows no errors ! they suggested BCU sent away for reprogramming, but from what I've read, is a partial BCU failure possible - seems to be the case that they go completely and the thing would just be totally immobilized ?

any thoughts much appreciated - ta everso !

My first action would be to decide which side is wetter; if it's the passenger's side then the BCU would be a better suspect but if it's the driver's side then it's more likely to be the IDM.
The IDM is contained on the back of the fuseboard under the steering wheel and does contain quite a number of relays, not easily changeable though, they tend to be soldered onto the circuit board.
Water can cause the printed circuit tracks to corrode and rot away or the "verdigree" which seems to grow on wet copper can cause untold problems.

+1^^^, in most cases the only way to rule these out is by replaceing the fusebox cos it's plug and play while the BCU needs complex programming on the vehicle and they both can cause similar symptoms, if you go for the fusebox get only pre-facelift one, even better same p/n if you find used, disconnect the battery before the swap and after reconnection turn ignition on II and let it so 5 minutes for digital data syncronisation with the BCU, then you can start the engine and see if things are fixed or not and if no joy you need a BCU

that's great chaps, thank you !

definitely soggier on the off-side, so fuse box swap over it is - they seem cheap enough, so far and away the best option first up - much appreciated

If it's that better fix that leak ASAP cos you might end up immobilised, untill then eventually get hold of some stuff like that http://www.nanoroad.co.uk/auto-coatings/4-nano-protech-electric.html and treat the fusebox and exposed conenctors with it, it's not cheap but worth it's weight in gold , i dont have shares in it believe me

+1 on the Nano-protect spray. Good stuff and designed for the job of moisture protection of circuits.
Also on fixing the leak(s). The attached files might help.

thanks very much for those attachments - the headliner cure(s) looks a bit more scientific that the current "loads of gaffer-tape all round the sunroof and down the drip rail" solution, which both looks a bit shoddy and has singularly failed to stop the leaks -