Market Size and the Rules Behind It
A connected vehicle exchanges data with other vehicles, the road, and people through an in-vehicle terminal, roadside equipment, and a cloud platform. The MIIT Guidelines for Building the Intelligent Connected Vehicle Standards System are pushing C-V2X (cellular vehicle-to-everything) into production. The China Society of Automotive Engineers reports that in 2023 the penetration of intelligent connected vehicles in China passed 42%, and factory-fit terminals shipped more than 20 million sets. iResearch expects the China market to pass 200 billion yuan in 2025, with a compound annual growth rate of about 18%.
Background and Pain Points
The market splits into factory-fit (installed by the OEM) and aftermarket (T-Box, OBD, dashcam, and similar). Factory-fit is mostly 4G/5G, and it carries remote control, OTA, vehicle-status reports, and FOTA (firmware over the air). Aftermarket covers fleet management, UBI (usage-based insurance), and used-car inspection. The hard parts: a stable link — coverage is uneven while the car moves, in an underground garage, and in remote areas; data security — vehicle status and location have to travel encrypted and be stored in line with the rules; switching operators — a trip across regions needs an automatic operator change if the car is to stay online.
Standards and Terms
The set includes GB/T 32960, Technical Specification for the Remote Service and Management System of Electric Vehicles, GB/T 26773, Vehicle Event Data Recorder System, plus C-V2X, LTE-V2X, and 5G-V2X. Terms in daily use: T-Box (telematics box); OBU (on-board unit); V2X (vehicle-to-everything); OTA/FOTA (over-the-air upgrade / firmware upgrade); M2M (device-to-platform communication); eSIM (embedded SIM). A T-Box uplink of 1–10 Mbps covers a status report and FOTA. Latency under 500 ms is what remote control needs. A C-V2X direct link is under 20 ms.
Who Builds It
The chain runs from T-Box makers (Quectel, Fibocom, Neoway Technology, and Neusoft) through carmakers (BYD, NIO, XPeng, and Li Auto) to connected-vehicle platforms (Huawei, Alibaba, and Tencent). Quectel and Fibocom lead the in-vehicle module share. Compared as connection methods, a single-operator SIM drops offline on a cross-province trip and in remote areas; multi-operator plus eSIM switching can lift the online rate by 5–8%. One new-energy carmaker put eSIM T-Boxes in 500,000 vehicles. Remote control and OTA succeed more than 99.5% of the time.
Where IoT Is Used
Factory-fit: Remote control, a vehicle-status report, a fault warning, an OTA, and in-car entertainment data. A new-energy car also reports BMS and charging state.
Aftermarket and fleets: A T-Box or OBD unit collects location, speed, fuel use, and driving behavior for dispatch, fuel management, and UBI.
Trucks, buses, and freight: The same link makes the trip visible, trims fuel use, and supports safety supervision.
Where the Market Is Heading
5G-V2X and C-V2X are being deployed at scale. Automated driving is being tied more tightly to the vehicle link. Vehicle-to-road pilots are widening. eSIM and multi-operator switching are becoming standard fit. The same data is being joined to insurance, finance, and the used-car record.
Summary
The vehicle link is the base layer for an intelligent car and for intelligent traffic, and the cellular connection has to hold. SimtoLink supplies 4G/5G IoT SIM cards and communication modules, with multi-operator switching and eSIM, so an in-vehicle terminal stays online around the clock for the carmaker and the network operator.