speedfight 2 spedometer panel

hello guys i want to ask 1 question about speedfight 2 (LC) spedometer panel there is 4 little bulbs (lights) (oil) (turn lights) (and some kind of shit xD ) soo i want to know what is that 4ourth bulb.... and why it is there ???


P.S sory for my English language skill xD x|

That's for some types that have an alarm system and then there is a flashing red led there
the ones with a chipkey i think