From Halopedia, the Halo wiki
The Genet is a compact, high-volume coupe, with several model trims ranging from eco-accessible, to track-ready. Like nearly all cars used in New Mombasa and elsewhere on Earth, the Genet includes roadware that allows the car to pilot itself while driving and keeps the car connected to the planet's surveillance grid.
Halo 3: ODST
Multiple types of Genets are seen abandoned on the streets throughout the campaign. The lights of the NMPD Genets in Mombasa Streets will flash to indicate points of interest, to indicate Audio Logs close by, for instance. Every Genet in the game has the same number on the left side of its side windows: 1031. Additionally, one Genet was seen at least partially destroyed due to passenger compartment damage, but lights were still functioning.
Halo: Spartan Strike
In Halo: Spartan Strike, the Genet appears on the streets of New Mombasa. The vehicle can be destroyed by using a Grizzly to run over it. This, however, will damage you due to the explosion that occurs when it is destroyed.
List of appearances