The ELM327 is the most popular OBD-II interpreter chip used in Bluetooth and Wi-Fi OBD-II dongles, translating between OBD-II protocols (CAN ISO KWP) and UART/SPI for smartphone diagnostic apps.
| Pin | Name | Function | Type |
|---|---|---|---|
| 1 | MFR_SPECIF | Manufacturer specific | I/O |
| 2 | J1850_BUS+ | SAE J1850 bus positive | BUS |
| 3 | MFR_SPECIF | Manufacturer specific | I/O |
| 4 | CHASSIS_GND | Chassis ground | GND |
| 5 | SIGNAL_GND | Signal ground | GND |
| 6 | CAN_HIGH | ISO 15765 CAN high | BUS |
| 7 | ISO_9141_K | ISO 9141-2 K-line | BUS |
| 10 | J1850_BUS- | SAE J1850 bus negative | BUS |
| 14 | CAN_LOW | ISO 15765 CAN low | BUS |
| 15 | ISO_9141_L | ISO 9141-2 L-line | BUS |
| 16 | BATTERY | Battery positive 12V | PWR |