Creating A Wireless OBDII Scanner

Project documentation for building a wireless OBD-II scanner — bridging vehicle CAN/OBD to a phone or PC over Bluetooth/WiFi.

Source

• JOHNKEENANIIIMQP2009.pdf — project report (local asset)

Typical build

Layer	Hardware / software
Vehicle	OBD-II port (ISO 15765-4 CAN or legacy K-line)
Adapter	ELM327 or STN1110 chipset on UART
MCU	Arduino/ESP8266/ESP32 for AT command bridge
Wireless	Bluetooth SPP or WiFi TCP server
Client	Serial terminal, custom app, or python-OBD

Flow

1. MCU powers from OBD pin 16 (+12V regulated)
2. ELM327 handles AT init and OBD mode 01 PID requests
3. MCU forwards serial ↔ wireless link
4. Client sends 010C (RPM), 010D (speed), etc.

Safety & legal

• OBD queries while driving can distract — bench-test first
• Do not transmit forged frames on public roads without authorization

Related

• OBD2 Guides
• ELM327 Datasheet
• Related Projects