b4 estate electrical problems

[sqweaka]

hi all, i think ive a B4 model its an engine code AFN am i right... ok
im guessing after reading about tthe wiring infront of the passanger seat, that this is the route my poeblem!
i have no interier lights, the elctric windows dont work, central locking via the key fob dont work, the alarm does'nt work, ive a warning light on the dash for low oil level but its reading fine on the dipstick, a warning for brakes keeps apearing aswell
ive had a quick look under the carpet and all seems very dry no sign of any damp, the wiring that comes from the box has a light blue powder over and under it in a small area where it turns back on itself to join the main part of the loom.. could this be where my problem is do you think?
any advice welcomed
ian