This is probably a case of a bad brake light switch inside the car (usually attached to the brake pedal mechanism itself). These switches can fail in the on or off position, leaving you with either no brake lights at all, or the problem you now have.

The good news is that it’s not a tough thing to fix, nor should it be expensive. The average mechanical workshop should be able to do it, and the new switch should be readily available from auto parts stores and online.

What you haven’t told me is whether your car has an automatic or manual transmission. And that means different things if the transmission has somehow been over-filled.

In the case of a manual gearbox, you’ll find that the extra oil will probably soon be evenly distributed across the bottom of your car as the excess exits the scene through either a breather tube or a seal or gasket.

But if it’s an automatic, the extra fluid could cause the entire transmission to behave strangely, as this type of gearbox relies on the correct internal fluid pressure to select gears, change gears and, in fact, make the car move at all. Again, though, the extra will probably force its way out through a seal or gasket and then you have a much more complicated repair to make.

The best advice is to check the level of the fluid as set out in the owner’s handbook and make sure the level is correct before driving anywhere else.

It sounds like the transmission has broken something internally. It could be that the clutch assembly is smashed, or the input or output shafts have snapped. It could even be the actual gearsets that have failed, leaving you with no mechanical connection between the engine and the gearbox.

Either way, it sounds like it needs a new clutch and/or gearbox which may be more than the market value of the car. That said, wrecking yards are full of Hyundai Getzes, so a second-hand, tested transmission might save the day.