ABS, water in electrics. ANY IDEAS?

[ELIMINATOR]

Help,
Pissed off with this. Twice after I have washed the bike with a hose, I have had problems. The bottom ABS light won't go out. First time this happened, I rode the bike a few miles, turned it off and on again. Bingo! All OK. Washed it yesterday, same problem, no better after a run. Went out today, after about 12 miles, turned it off and on again, OK.
Question, where is the water getting in? How do I seal it? OK perhaps I should be more carefull with the hose, but Charlie & Ewan weren't!

 

[ELIMINATOR]

Update.
Left for work this morning, bloody light on without me having washed the bike within the last 5 minutes.
I had previously checked the brake light bulb, as I had read that the filament breaking causes the bottom ABS light to stay on. What I didn't realise was that if the bulb fails, then the clever system uses the other filament as both tail & brake light. Maybe you knew this?
Thanks to Les at SPC, more so as I went in and instantly engaged grumpy customer mode. Les explained patiently how it works.

The assumption is that sometimes the filament connected & other times it didn't. Struggled to see the break.