How to Connect an OBD2 Adapter to inCarDoc via Bluetooth or Wi‑Fi

To use inCarDoc for vehicle diagnostics, you need a compatible OBD2 adapter connected to your car’s diagnostic port. Depending on your mobile device and adapter, the connection can be established through classic Bluetooth, Bluetooth Low Energy (BLE), or Wi‑Fi.

This guide explains how to connect:

• An Android smartphone or tablet via Bluetooth, BLE, or Wi‑Fi
• An iPhone or iPad via Bluetooth Low Energy (BLE) or Wi‑Fi
• The inCarDoc app to an ELM327-compatible OBD2 adapter

It also covers the most common connection problems and explains how to send diagnostic logs to inCarDoc Support.

Before connecting the adapter

Make sure you have:

• A vehicle that supports the OBD‑II standard
• A compatible ELM327-based OBD2 adapter
• The latest version of the inCarDoc app
• Bluetooth or Wi‑Fi enabled on your phone or tablet
• All permissions requested by the app
• The vehicle parked safely with the parking brake applied

Your vehicle’s OBD2 port—also called a Diagnostic Link Connector or DLC—is usually located under the dashboard, within approximately 60 cm (2 feet) of the steering wheel. In some vehicles, it may be hidden behind a small cover marked “OBD‑II” or “Diagnosis.”

OBD2 and adapter compatibility

Is your car compatible with OBD2?

As a general guideline, OBD‑II is supported by:

• Most vehicles sold in the United States from 1996
• Most European petrol vehicles from 2001
• Most European diesel vehicles from 2004
• Many Japanese vehicles from 2005

The presence of a 16-pin diagnostic port alone does not always confirm full OBD‑II compatibility. Check your vehicle documentation or look for an “OBD‑II compliant” label if you are unsure.

Choosing a compatible adapter

Android devices can work with many ELM327-based interfaces, including OBDLink, Vgate, Kiwi, and other compatible Bluetooth, BLE, or Wi‑Fi adapters.

For an iPhone or iPad, choose an adapter that explicitly states that it supports Bluetooth Low Energy, BLE, iPhone, iPad, or iOS. Compatible options may include OBDLink MX+, Kiwi BLE, BLE versions of Vgate adapters, and similar iOS-compatible interfaces.

How to connect Android via Bluetooth

Android may support both classic Bluetooth and BLE. Select the mode that matches your adapter.

1. Plug in the adapter

   Insert the Bluetooth OBD2 adapter firmly into the diagnostic port. Confirm that the adapter’s power indicator is illuminated.

2. Start the engine

   Start the vehicle so the adapter is powered and the electronic control unit is available.

3. Enable Bluetooth and permissions

   Turn on Bluetooth in Android settings. Allow Nearby devices, Bluetooth, and Location permissions if Android requests them. Some Android versions also require Location services to be on while scanning for nearby devices.

4. Pair a classic Bluetooth adapter

   Open the phone’s Bluetooth settings, find the adapter, and select it. If a PIN is requested, try 1234 or 0000. The adapter may appear as OBDII, OBD2, ELM327, V-LINK, Vgate, or its manufacturer’s name.

   BLE adapters generally do not require pairing in Android system settings unless the manufacturer specifically instructs you to pair them.

5. Select the adapter in inCarDoc

   Open inCarDoc and go to Settings → Connection → Connection Type. Select BT for classic Bluetooth or BLE for Bluetooth Low Energy. Choose your adapter from the list.

6. Connect to the car

   Return to the Home screen, tap Connect, and wait for the test to finish. Once inCarDoc connects to both the adapter and the ECU, you can begin diagnostics and view live data.

For the first connection, you can also open Settings → Connection Guide and follow the guided setup.

How to connect Android via Wi‑Fi

A Wi‑Fi OBD2 adapter creates its own local wireless network. Your phone must remain connected to that network while you use inCarDoc.

1. Install and power the adapter

   Plug the Wi‑Fi adapter into the OBD2 port, start the engine, and check that the power indicator is on.

2. Join the adapter’s network

   Open Android Wi‑Fi settings and select the network created by the adapter. If Android warns that this network has no internet access, choose to remain connected. Check the adapter manual if a password is required.

3. Select Wi‑Fi in inCarDoc

   Go to Settings → Connection → Connection Type and select Wi‑Fi.

4. Check the connection settings

   Common default values are:

   • Adapter IP address: 192.168.0.10
   • Port: 35000

   These values are not universal. Use the IP address and port provided by the adapter manufacturer if they differ.

5. Connect to the vehicle

   Return to the Home screen, tap Connect, and wait until the app detects the vehicle’s ECU.

How to connect iPhone or iPad via BLE

iOS and iPadOS do not support the classic Bluetooth connection used by many generic Android ELM327 adapters. You need an adapter that is explicitly compatible with BLE and iOS.

1. Plug in the BLE adapter

   Insert the adapter into the vehicle’s OBD2 port and confirm that it is powered.

2. Start the engine

   Start the vehicle so its ECU is available for diagnostics.

3. Turn on Bluetooth

   Open iPhone or iPad Settings → Bluetooth and switch Bluetooth on. Most BLE adapters are selected inside inCarDoc and do not require manual pairing in iOS settings.

4. Allow Bluetooth access

   Open inCarDoc and allow Bluetooth access when requested. You can review the permission under Settings → Privacy & Security → Bluetooth. Make sure inCarDoc is enabled.

5. Select the BLE adapter

   In inCarDoc, go to Settings → Connection → Connection Type, select BLE, and choose your adapter.

6. Start diagnostics

   Return to the Home screen, tap Connect, and wait for the connection test to finish before opening diagnostic features.

How to connect iPhone or iPad via Wi‑Fi

1. Plug in the Wi‑Fi adapter

   Insert the adapter into the diagnostic port and start the engine.

2. Join the adapter’s network

   Open Settings → Wi‑Fi, select the network created by the adapter, and enter its password if required. Stay connected even if iOS reports that the network has no internet connection.

3. Configure inCarDoc

   Go to Settings → Connection → Connection Type and select Wi‑Fi. If the values are not detected automatically, check the adapter IP address and port. Common values are 192.168.0.10 and 35000.

4. Configure a static IP only if required

   Most adapters do not require manual network configuration. If your adapter specifically requires it, open the information screen for the adapter’s Wi‑Fi network, choose Configure IP → Manual, and enter a phone IP on the same network, such as 192.168.0.11, with subnet mask 255.255.255.0.

5. Connect to the vehicle

   Return to the inCarDoc Home screen, tap Connect, and wait for the app to detect both the adapter and the ECU.

Why inCarDoc cannot connect

If there is no connection between the phone and the adapter, one of the following may be the cause:

• The adapter is not receiving power, is faulty, or is incompatible.
• The wrong connection type is selected in inCarDoc.
• An old adapter remains selected after the adapter was replaced.
• Another phone or app is already using the adapter.
• Bluetooth or Wi‑Fi has stopped responding.
• Required permissions were not granted.
• The phone automatically joined another Wi‑Fi network.
• The adapter uses a different IP address or port.
• A low-quality ELM327 clone does not support the required commands.

Connection troubleshooting checklist

1. Park the vehicle safely and start the engine.
2. Unplug the adapter and plug it back in.
3. Confirm that its power light is on.
4. Close other diagnostic and OBD2 apps.
5. Make sure no other phone or tablet is connected to the adapter.
6. Restart Bluetooth or Wi‑Fi on your phone.
7. Restart the phone if necessary.
8. Open Settings → Connection → Connection Type.
9. Select the correct Bluetooth, BLE, or Wi‑Fi mode.
10. Select the adapter currently installed in the vehicle.
11. Open Settings → Connection Guide and repeat the test.
12. Wait until the app either connects or displays an error.

For Android classic Bluetooth, you can also try changing the Bluetooth mode in the connection settings. For example, switch the BT mode to Secure and repeat the test.

For Wi‑Fi, confirm that the phone is still connected to the adapter’s network. Mobile devices may switch to another Wi‑Fi network or mobile data because the adapter network does not provide internet access.

The adapter connects, but the ECU is not detected

A Bluetooth or Wi‑Fi connection only confirms communication between the mobile device and the adapter. inCarDoc must then establish a separate connection between the adapter and the vehicle’s ECU.

If the adapter connects but the ECU is not found:

• Make sure the engine is running.
• Confirm that the adapter is fully inserted into the OBD2 port.
• Check whether the vehicle supports the OBD‑II standard.
• Close other apps connected to the adapter.
• Restart the adapter and repeat the test.
• Check whether the adapter supports your vehicle’s OBD protocol.
• Try a reliable adapter if you are using an inexpensive ELM327 clone.

How to send a connection log

If the problem continues, enable debug logging before you repeat the connection test:

1. Enable debug logging

   Open inCarDoc → Settings → Logging and enable Debug logging.

2. Repeat the failed connection

   Return to the connection screen, try to connect again, and wait until an error message appears.

3. Send the log

   Return to Settings → Logging, select Send message or Send, add a short description of the problem, and send the generated log.

Frequently asked questions