Julie, TL1, and TL2, are the connections for the Tail Light, when you turn the standard Ign switch to off (first position) everything is disconnected, and the key can be removed. On (second position) switches the tail light on if the lights are switched on, the key cannot be removed; and park (third position) switches off the Ignition and Headlights but leaves the front parking light on if fitted; and the tail light on. The key can be removed.
Hope this answers your question!
Nigel.