Motion tracker

Spartans and Elites have a Motion Tracking Sensor built into the HUD of their helmets and armor. The sensor shows friendlies as yellow blips and friendly vehicles as large yellow blips. Enemies are shown as red blips, Hunters and enemy vehicles as large red blips. The motion tracker will show how close they are in relation to your current position, up to 25 meters. When someone on the other team in multiplayer speaks, their red blip is surrounded by a white glow and it becomes bigger. Nav points will also show up, shown only as a small white triangle at the end of the sensor.

The motion tracker is not a radar. Slow moving enemies will not show up on the sensor. This can work to your advantage of course, moving very slowly or crouch walking will mean you won't show up on enemies motion trackers.

Trivia

 * In Halo 3 custom games or Forge, the motion sensor can be increased its range by 15 metres, 25 metres, 50 metres or even 150 metres.