Pair scanner

Pair, read, and review your car's codes.

Plug a Bluetooth OBD-II dongle into the port under your dash, turn the ignition to ON, and pair it from Chrome. CrankKey attempts the standard VIN read, checks the responder paths the adapter exposes, reads stored codes, and builds a source-qualified report with honest limits. Start the live stream when you are ready to watch rolling RPM, temperature, speed, and fuel trim graphs. When Garage has an exact supported vehicle and the stream shows a clear warm idle or steady cruise, CrankKey adds a conservative normal-range comparison; ambiguous context stays Unknown instead of guessing.

Web BluetoothNo app to installReport is transient and not persisted

Rescanopens Chrome's Bluetooth picker and pairs a freshly chosen dongle. Reconnect last device only appears once you've paired at least one dongle on this page.

Live scan map

Module check
Ready
Connect a BLE adapter to map the responder paths before reading stored codes.

No module results yet

Nothing is checked until a BLE adapter is connected. Use Pair scanner above when the dongle is plugged in and the ignition is ON.

Rolling telemetry

See the engine think in real time.

Each trace keeps the last 30 seconds of valid readings in this browser tab. The graph never stores or uploads vehicle data.

Ready to stream
Engine speed
Last 30 seconds
—rpm
Engine speed over the last 30 seconds700035000
No engine speed reading in this window
No reading yet0–7000 rpm
Coolant temperature
Last 30 seconds
—°C
Coolant temperature over the last 30 seconds14050-40
No coolant temperature reading in this window
No reading yet-40–140 °C
Vehicle speed
Last 30 seconds
—km/h
Vehicle speed over the last 30 seconds2001000
No vehicle speed reading in this window
No reading yet0–200 km/h
Short-term fuel trim
Last 30 seconds
—%
Short-term fuel trim over the last 30 seconds300-30
No short-term fuel trim reading in this window
No reading yet-30–30 %
Long-term fuel trim
Last 30 seconds
—%
Long-term fuel trim over the last 30 seconds300-30
No long-term fuel trim reading in this window
No reading yet-30–30 %

The report is transient. The raw snapshot stays in this browser for review; the report request is validated and enriched, then discarded rather than persisted or logged.

Raw response from the dongle
Nothing yet — connect a dongle to see the full reply.

How the read works. After you pick the adapter from the system Bluetooth picker, the page opens a GATT connection, subscribes to the dongle's notify characteristic, attempts VIN capture, checks standard capability and stored-code paths, then preserves any ECU address the adapter provides. Enhanced ABS, SRS, and body access is only shown when the adapter exposes a compatible path.

If you have a WiFi-only dongle. Chrome can't open the raw TCP socket those adapters advertise (192.168.0.10:35000-style). Use the vendor app to read, then drop the codes in the lookup at /. The list of supported BLE-compatible dongles lives on the page above.

Reports are transient. The browser keeps the raw snapshot for review, while the report request is validated and enriched without persisting or logging the scan.

Streaming is explicit. Use Start streaming after pairing, and Stop streaming whenever you want to hold the last graph points on screen. A stale banner appears when the dongle stops replying.