NAVGPS

How-To

Connect the OBDLink MX+ and read live engine data

NavGPS reads live engine data through an OBDLink MX+, which connects over Apple's MFi Bluetooth rather than Bluetooth LE. That changes the pairing steps, so they are worth following in order.

Before you start

  • An OBDLink MX+ adapter
  • A vehicle built in 1996 or later (when OBD2 became mandatory in the US)

Steps

  1. Plug in the adapter
    Find the OBD2 port — usually under the dash on the driver's side — and plug the MX+ in. Turn the ignition on.
  2. Pair it in iOS Settings
    Open iOS Settings → Bluetooth and pair the OBDLink. This step is required: the MX+ is a classic Bluetooth MFi accessory, so it must be paired at the system level first.
  3. Close any other OBD app
    The adapter talks to one app at a time. Force-quit the OBDLink app, Torque, or anything else that may have claimed it.
  4. Tap Connect
    Open the Engine tab in NavGPS and tap Connect. The first reading takes about ten seconds while the adapter works out how your vehicle talks.
  5. Identify the vehicle
    NavGPS reads the VIN and offers to save the vehicle, so readings, calibration and fuel settings are remembered per truck. Turn on Auto-Connect under Vehicles and it reconnects next time by itself.
The NavGPS engine dashboard reading live data from an OBDLink MX+
Once connected, the Engine tab reads live and logs against your track.

Worth knowing

  • If the adapter does not appear, the Diagnostics screen lists every accessory iOS is offering the app and what each one advertises — that is the fastest way to see what is actually connected.
  • With no adapter connected the Engine tab says so. It never shows invented numbers: a gauge cluster that makes values up is worse than none.