USB or Bluetooth: pair Bluetooth ELM327 adapters in your OS Bluetooth settings first (they show up as a serial/COM port) — then use Connect (Serial) below for either. Connect (BLE) is a separate best-effort path only for adapters that speak Bluetooth Low Energy natively.
Disconnected
Live Gauges
O2 Sensor Voltage — rolling 10s
Waiting for connection to detect wideband / narrowband sensors…
Custom Sensor Widgets
Diagnostic Trouble Codes
Historic / Pending Codes — Mode 07
"Historic" isn't a single standardized OBD-II mode — this uses Mode 07 (pending codes), detected during the current or last drive cycle but not yet confirmed as stored faults.