OBD2 diagnostics · Lugnut Pro

An OBD2 app that keeps the history

Most code readers show you a code and forget it. Lugnut saves every check with the vehicle, next to its service records, so you can see when a code first appeared and whether a repair fixed it.

What it reads

• Diagnostic trouble codes, stored and pending, with a plain-language description.
• Readiness monitors, useful before an emissions test.
• 12-volt battery voltage, with a trend over time so a weak battery shows up before it leaves you stranded.
• The odometer, on vehicles that report it, to keep reminders on schedule.

Lugnut only reads. It doesn't clear codes or change any settings in the car.

Automatic checks when you start the car

Turn on automatic checks and leave the adapter plugged in. When the car starts, your iPhone reconnects in the background and runs a check. You don't need to open the app. If a new code appears, you get a notification.

Which adapters work

Lugnut works with Bluetooth LE adapters of the ELM327 type, such as the Vgate iCar Pro BLE and the Veepeak BLE. iPhones can't connect to adapters that use only classic Bluetooth, so check that the adapter says BLE or Bluetooth 4.0 or later. Some adapters drain the battery if left plugged in for days; check the maker's instructions.

Already use another OBD app?

Lugnut can import a scan tool's report as a PDF or photo, and CSV data logs from apps such as BimmerLink, OBDLink and Car Scanner. You can also choose a folder those apps sync to, and new logs are added automatically.

Try it without an adapter

Open a vehicle's Diagnostics page and tap Try a Demo Check to see a sample result.