ESP32 OBD Scanner project

Background

Having a few years working in automotive service, one aspect of vehicle repair that has piqued my intrest is the electronic systems within cars. Having used multiple different commercially available OBD scanners (from simple OBD2 standard scanners, ELM327 based scanners, to the professional Autel or Snap-on devices), I wanted to take a crack at seeing what goes into one of these devices.

Overall, I am quite disappointed in the commercially available non-professional OBD scanners on the market. The inability to send vehicle specific commands when diagnosing vehicle issues makes it very difficult to pinpoint issues where having a professional scanner with the ability to command modules can make the process easier. A goal of the project is to be able to send commands (which, for example, none of the ELM 327 devices I've used have been able to.

Why an ESP32?

The ESP32 is a fantastically powerful and versatile device, while being very inexpensive for the power it provides. Having an integrated CAN controller makes it an easy option to interface with CAN busses, simplifying the electronics hardware needed, overall reducing the cost and complexity of the project. As well, with the ESP32 running a Real-time OS (RTOS) makes it perfect for this use case, as OBD interfaces are constricted by timing, and anything outside of this strict timing may result in the CAN controller dropping frames.

This project as well relies on an ESP32 development board which integrates voltage regulators, simplifying the work needed to get the electronics functioning.

An additional benefit to the ESP32 is the built-in bluetooth and Wi-Fi, possibly leading to a future phone application to interface with the project.

Discalimer

It should be mentioned that anything within this project is extremely experimental. If you decide to go through and produce this project yourself, be aware that using it with a live vehicle may result in damages, possibly up to damaging your vehicles ECU. You have been warned!