Was a Vehicle electrician in the army.
In Belfast in 2003 when we had to prep all the snatch landies that were spare so they could be sent to Basra. Had a
Sparkie straight out of training who constantly came over to ask how to do this and that. I decided to get rid of him for an hour or 2 so I could crack on. Changed the side light and indicator rubies over on a snatch over the far side of the vehicle park. Told him the side lights were flashing when the indicators were on and the indicators were staying on permanent. Didn't see him for 4 hrs. He still hadn't figured it out.
Out in Norway I was bored, so while my mate the mechanic was servicing a BV206 I thought it would be a great laugh to wire the brake lights to the horn. You could turn it off with a wee switch under the dash. Anyways dropped the wagon off with the battery and flicked the switch. Turns out it was the CO's. After a day being driven around the ranges, he was nearly deaf. When I got posted out of the unit I went up to the hanger and flicked the switch again.