It means there's an active Data Trouble Code pertaining to the transmission, and you'll need to have a diagnostic link connected to determine exactly what it is.
Best to use the Honda coolant 50/50 mix.
If you mean the tombstone of L and D (Life and Death) Before you do anything press ctrl+shift+c and then ytpe in boolProp testingCheatsenabled true (EXACTLY like that) then go to your sim, hold shift and click your sim. Then click spawn and choose tombstone of L and D and theres your cheater tombstone!
Advantages over other bridge typesLonger main spans are achievable than with any other type of bridgeLess material may be required than other bridge types, even at spans they can achieve, leading to a reduced construction costExcept for installation of the initial temporary cables, little or no access from below is required during construction, for example allowing a waterway to remain open while the bridge is built aboveMay be better to withstand earthquake movements than heavier and more rigid bridges