Just returned home from trip to Lake District (don't ask about the weather) and have experienced an intermittent fault on left indicator. When hitching up and doing the lights test before setting off, no problem. While travelling, Left indicator on van will not cancel but car does. Also, bleeper sounds continuously. Only way to cancel is to indicate Right. Doesn't happen every time and visual inspection of bulbs and contacts shows no problem. All other lights are fine. Anyone have any ideas? All suggestions gratefully received and thanks in advance.