==== SPATEM (Signal Phase and Timing Extended Message) ====
SPATEMs transmit the **current state of a traffic light** (ETSI TS 103 301): which signal groups are red, amber, or green right now — and how the state is expected to change.

A SPATEM contains, among other things:
  - the current phase per signal group (red / amber / green)
  - predicted change times (e.g. "likely green in 12 s")
  - references to the intersection topology from [[en:c-its:messages:mapem|MAPEM]]

SPATEMs are sent by C-ITS traffic lights ([[en:c-its:rsu|RSUs]]), typically several times per second. Together with MAPEM they enable time-to-green displays and speed advisories (GLOSA) — this is what some vehicles show as traffic light information.