It was an attempt at humor. 1986 was probably the nadir of Jaguar reliability, and that is saying something. They slid into the end of the 1980’s as a failing venture and were bought by Ford for a song. Ford lost $billions over the next two decades before unloading them to Tata - which seems to have turned it around as a brand. But in the 1980’s they were terribly unreliable.
I heard that Ford required them to use their wiring harnesses rather than Lucas . . . our TR-6 only caught on fire TWICE . . . til we discovered the dead short that was IN THE SCHEMATIC. You couldn’t invent this stuff!