This short story happened to me many years ago, although bench based most of the time I was occasionally required to help in the field at busy periods. This day I received a call to go and look at a faulty remote control, the set was based on a Thorn 9650 series and the remote was a type T720 which we repaired to component level even in the field. We carried everything for them, ICs, button matrix, case parts etc.
On arriving at the customers home I was told that the RCU didn’t function at all, certainly the red LED on the handset didn’t light when any buttons were pressed. Knowing that customers often tell porkys about having replaced the batteries I reached for my meter and looked for 6v coming from the battery compartment.
Well, my meter indicated around 1.8v and I asked if new batteries had been tried? “Nowt wrong with them batteries son” came the reply in a broad Geordie accent. “But I’m seeing they are virtually flat on my meter” I replied. “Look son, there’s nowt wrong with them batteries” he replied again, “If you look at the label you’ll see them batteries don’t run out till 1986” which was some 3 years hence.
I was about to laugh out loud at his little joke but by his expression I could see that he was deadly serious, at this point I had a rummage in the car and found some good AA Duracell types and fitted them, hey presto. Next came an explanation to him about the shelf life date on the labels.