Start from a template
Basic Safety Message (BSM)
messageId 20 85 bytes BasicSafetyMessage The BSM is broadcast by every connected vehicle up to 10 times per second and carries its current position, motion and basic status (Part I coreData) plus optional Part II extensions. This example shows a passenger car travelling east at 15 m/s on Broad St in Falls Church, VA with no brakes applied, a 3-point path history, a straight-line path prediction and low-beam headlights plus daytime running lights on.
Signal Phase and Timing (SPaT)
messageId 19 164 bytes SPAT SPaT is broadcast by a roadside unit at a signalized intersection (typically 10 Hz) to report the current state and expected timing of every signal group listed in the matching MAP message. This example describes intersection 1201 (Broad St & West St, Falls Church, VA) with four signal groups: eastbound through (green), northbound through (red), and two pedestrian crossings (one walk, one don't walk).
MAP (Intersection Geometry)
messageId 18 323 bytes MapData The MAP message describes the geometry of an intersection: a reference point and a set of lanes built from node offsets, with per-lane attributes, allowed maneuvers and connections to downstream lanes tagged by signal group. This example describes intersection 1201 (Broad St & West St, Falls Church, VA) with an eastbound and a northbound ingress/egress pair and two crosswalks, consistent with the SPaT template.
TIM - Work Zone Advisory
messageId 31 128 bytes TravelerInformation A Traveler Information Message carries advisory, road-sign or work-zone information for a geographic region over a time window. This example is an advisory frame for a work zone on westbound Leesburg Pike (VA-7) near Gallows Rd in Tysons, VA: the region is a 3-segment path along the roadway and the content is a list of ITIS codes (road construction, reduced to one lane, narrow lanes) plus free text.
TIM - Speed Limit Sign
messageId 31 109 bytes TravelerInformation A second TIM variant that presents a regulatory speed limit sign for a stretch of westbound Leesburg Pike in Tysons, VA using the speedLimit content type. The region path and timing fields work exactly like the work-zone advisory; only the frameType, MUTCD code and content differ.
Road Safety Message (RSM) - Work Zone
messageId 33 164 bytes RoadSafetyMessage The J2945/4 Road Safety Message is the newer, structured replacement for work-zone TIMs: a commonContainer identifies the event (ID, times, ITIS cause) and its reference region, and one or more content containers describe specific conditions. This example describes a work zone on westbound Leesburg Pike in Tysons, VA with a 45 mph reduced speed zone and a closure of lane 2.
Personal Safety Message (PSM)
messageId 32 54 bytes PersonalSafetyMessage The PSM is broadcast by a vulnerable road user device (phone, wearable, or an RSU acting on their behalf) so that vehicles can detect pedestrians, cyclists and workers. This example is a pedestrian walking north at 1.4 m/s toward the Broad St & West St intersection in Falls Church, VA with a short path history and a pending crossing request.
Signal Request Message (SRM)
messageId 29 66 bytes SignalRequestMessage An SRM is sent by a vehicle (typically transit or emergency) to ask a signal controller for priority or preemption on a specific approach. This example is Metrobus route 28A approaching intersection 1201 (Broad St & West St, Falls Church, VA) northbound on lane 3 and leaving on lane 4, requesting transit priority.
Signal Status Message (SSM)
messageId 30 36 bytes SignalStatusMessage The SSM is the signal controller's reply to one or more SRMs, reporting the status of each active priority/preemption request so the requester (and other vehicles) know whether it was granted. This example is the controller at intersection 1201 granting the transit request from the SRM template.
Sensor Data Sharing Message (SDSM)
messageId 41 84 bytes SensorDataSharingMessage The J3224 SDSM lets an RSU or equipped vehicle share objects it has detected with its own sensors (radar, lidar, camera) so that unequipped road users become visible to connected vehicles. This example is an RSU at Broad St & West St, Falls Church, VA reporting one eastbound passenger car about 45 m west of the RSU and one pedestrian near the southwest corner.
Emergency Vehicle Alert (EVA)
messageId 22 46 bytes EmergencyVehicleAlert The EVA wraps a RoadSideAlert with emergency-vehicle details so that nearby vehicles can yield. This example is an ambulance on an emergency run heading west toward Falls Church, VA with siren and lights active, alerting traffic within 1000 m.
RTCM Corrections
messageId 28 50 bytes RTCMcorrections RTCMcorrections lets an RSU relay raw RTCM 3.x differential GNSS correction frames over V2X so vehicles can improve their positioning. This example carries a single, CRC-valid RTCM 3 message type 1005 (stationary reference station ARP) for a base station at Broad St & West St, Falls Church, VA, with the GNSS status flags and antenna offset header.
Random valid example
Any of the 1,218 schema types, structurally valid (values are random).
Type name