> For the complete documentation index, see [llms.txt](https://navixy.com/docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://navixy.com/docs/expert-center/vehicle-telematics-technology/can-and-obdii.md).

# CAN and OBDII

GPS devices read engine data and fault codes via CAN bus and OBD-II. Covers DTC decoding, communication protocols, and OBD device fundamentals.

This section explains how GPS devices communicate with vehicle electronics through CAN bus and OBD-II interfaces, covering the protocol landscape, plug-and-play OBD devices, and how to read and interpret diagnostic fault codes.

## Contents

* [Intra-vehicle communication: CAN, FlexRay, and MOST](/docs/expert-center/vehicle-telematics-technology/can-and-obdii/intra-vehicle-communication-can-flexray-and-most.md): How ECUs exchange data over different in-vehicle network protocols.
* [OBD device fundamentals](/docs/expert-center/vehicle-telematics-technology/can-and-obdii/obd-tracker-fundamentals.md): How plug-and-play OBD devices connect to the diagnostic port and what data they expose.
* [DTC (Diagnostic Trouble Codes)](/docs/expert-center/vehicle-telematics-technology/can-and-obdii/dtc-diagnostic-trouble-codes.md): How to decode fault code structures, interpret error categories, and act on diagnostic data.


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