Node:Reset Vehicle Data, Next:Pre-signal removal, Previous:Purchase list modifications, Up:Sign Cheats (detailed)
Cht: ResetVehicles
Cht: ReloadEngines (obsolete)
Normally, it is not possible to change a vehicle's date of introduction or the climates in which it is available in a savegame. All such changes (for example using TTD Alter or the "newships" switch) are only available after starting a new game.
With this sign cheat however, all values are reloaded and all modifications are included in the current game. Note that this may also cause some vehicle types, including those you're using, to disappear from the market. The vehicles you have already bought are safe, though. If a vehicle type disappears that you would like to be available, you may use the Cht: AllVehicles cheat to make all vehicle types available. This, however, will not work if an alternative vehicle set (see New Graphics), in which your vehicle type does not exist, is loaded.
Reliabilities, introduction dates, names and other properties of vehicle types are also reset when you use this cheat.