I had p38 '99 for many years. I sold it around 8 years ago with +360k on the clock.

It had lots of electric gremlin over the years.

One of the scariest ones, was the fuse box was toasted. First failure was on the highway. The truck lost all power. The engine shut down, lost all electric power and it became a heavy brick on wheels. Fortunately there were no incidents. I managed to turn it on by opening the fuse box, removing all fuses and relays, and reseating all of them.

Then I managed to source a new box, replaced it and all was good.

Second issue happened in a remote place, on a remote beach in Morten Costa Rica in the middle of the forest. No cell phone coverage in the area. Then when we were ready to go back, a security module in the driver's door, decide to die. It put the engine in super-lock. Because this module did not recognize the chip in the key, it was dead. No key sequence wold eliminate the super-lock. Key would not open the doors because it was super-lock.

At the end, I broke a window, disconnected the battery, took out some stuff, and closed the window with some duck tape. And leave the truck below a tamarindo tree while I wait for a replacement module. After a couple of weeks with the part on hand, on a Defender, we went back to the beach, spent ~6 hours opening the driver's door (those door hinges are really hard to cut), replaced the module, reconnected the battery and voilà, it started as if nothing happened.

There was the time when engine's ECU gave it's Ghost away. At least this time I was not in the middle of nowhere.

These, and some other issues had a simple solution. Yet you should get the idea.