I tested this "Low Fuel" orange lamp and the computer's indicator or remaining autonomy.
At about 48 kms remaining (according to the on-board computer), the autonomy meter changes to low fuel instead of the remaining kms. I checked this for 3 tanks now. And this is a bit too much conservative. The real remaining autonomy is about 75 kms, maximum from my deductions but it's hard to test.
At about 8 liters (they say so in the driver's manual, and it's about real, I checked when I refueled) remaining in the fuel tank, the orange indicator in the dash lits up letting you know that the fuel tank is about empty. Personally, I don't think 8 liters is very low, but then, its my opinion.
So if you do about 12,5 liters or so per 100 km, the real remaining autonomy is about 64 kms.
The most I filled up is 51.7 liters (the tank is 51.1 liters. The 0.6 liter overfill must be the fuel pipe from the tank to the place I put the fuel pump) and the motor did not miss fire at all on my way to the gas station, but I'm pretty sure it was very close to doing so since the fuel was so low.
In other words, add about 30 kms or so to the remaining autonomy from the on board computer and you're about it.