Regarding the Ford Focus indicator fault discussed in Help!
(CM, May 2018), this seems very similar to a problem I had with both the left- and right-hand indicators in my 2006 Focus within about a year of each other. The cause was the same on both sides: the positive contact in the bulb holder had lost tension over the years, so it was no longer making contact with the bulb. In both cases, with the bulb removed, I simply tweaked the contact slightly towards the bulb, which restored power and I have had no problems since then.
As this happened on both my rear indicators, I’m assuming it’s a common fault – unless I’ve been particularly unlucky!