As I was driving my car on the usual daily commute, I noticed the dashboard started dimming as my blinkers were blinking. Scared as to what could've caused this, I stopped and opened the hood where I was greeted by a loose positive battery terminal. This was after around 500-600 meters.
I immediately replaced it as it was very corroded but I wonder if this has done any damage to the car electronics below the surface? Car seems to run fine otherwise. It's a 2003 diesel.
More than likely you've not caused any issues if none exhibited themselves after replacing the battery terminal.
To answer your question, though, it could have cause huge issues for you. There are two things which may have happened (that I can think of off the top of my head):
First, if the cable clamp came in contact with a grounded source, you could have fried everything in your car (think thermal nuclear meltdown of the positive wire).
Second, the battery acts as more than a power source, it also acts as a buffering device. As a buffering device, it takes up the shock from the electrical system when there are spikes or dips in voltage being. This helps protect all of the electronic equipment in the car. Without the battery being attached to it, you run the risk of damaging some, if not all of the equipment.
Since your car seems to be running/acting just fine, I'd suggest you got off lucky. Really, electronic issues would more than likely exhibit themselves right away, so I don't think you'll have any issues at this point.
