“Wait—why does my new OBDII dongle show up, but won’t connect in OBDAI?”
If you’ve found yourself asking this, you’re not alone—and the answer is all about Bluetooth types. In this post, we’ll explain the difference, why some adapters work out of the box and others need pairing, and how you can easily connect a Classic Bluetooth adapter to OBDAI on Windows.
Bluetooth Classic vs Bluetooth LE (Low Energy): What’s the Difference?
There are two major types of Bluetooth used by OBDII dongles:
- Bluetooth LE (BLE) (a.k.a. Bluetooth Smart):
- Introduced in Bluetooth 4.0.
- Does not require pairing in most cases.
- Used by modern adapters like the Vgate iCar Pro BLE.
- Fully supported in OBDAI on Android, Windows, and iOS.
- Bluetooth Classic:
- Older, legacy technology still common in ultra-cheap adapters.
- Requires pairing via system settings.
- Appears as a virtual COM port after pairing.
- Used by many white-label dongles sold on AliExpress or eBay for a few bucks.
When OBDAI first launched, we prioritized BLE support because it’s the dominant standard across platforms—especially in the US, where most new dongles default to BLE. At the time, we hadn’t encountered a single Classic-only device.
But now we have.
Why Classic Bluetooth Isn’t Supported on iOS
This is Apple’s doing, not ours.
iOS strictly limits access to Bluetooth Classic Serial Port Profile (SPP). Unless the accessory is part of Apple’s Made-for-iPhone (MFi) program, iOS simply will not allow the connection. Apple prioritizes BLE and uses it for nearly all third-party communications.
Bottom line: Classic Bluetooth adapters will never work with OBDAI on iOS. You’ll need a BLE-compatible dongle.
What About Android?
Great news: Classic Bluetooth support is coming to Android in the next OBDAI release.
This will include:
- Bonded device discovery
- Support for COM-style connections via SPP
- Seamless fallback if BLE scan fails
You’ll be able to connect a $3.19 adapter or a premium Veepeak, no problem. Stay tuned—we’ll announce the release across all platforms soon.
How to Connect a Classic Bluetooth Adapter to OBDAI on Windows
If you’re using Windows, Classic Bluetooth adapters are already supported—just not through the BLE interface. Here’s how to connect:
Step 1: Pair Your Adapter in Windows Settings
- Open Windows Settings → Bluetooth & Devices.
- Turn on Bluetooth and put your adapter in pairing mode.
- Look for a device named something like
OBDII,ELM327, or similar. - Click Pair.
Windows will silently create COM ports for the adapter (e.g., COM3, COM5, COM7).
Step 2: Identify the Right COM Port
- Open Device Manager (
Win + X→ Device Manager). - Expand Ports (COM & LPT).
- Look for entries labeled:
Standard Serial over Bluetooth link (COMX) - If multiple ports show up, start with the lowest number (e.g., COM3).
- Plug that port into OBDAI’s Connection Type → USB → COM Port box.
Yes, we know—it says “USB.” That’s just our catch-all for any serial port, including Bluetooth ones.
Step 3: Connect in OBDAI
- Launch OBDAI.
- Select Connection Type: USB.
- Enter the COM port number you identified (e.g.,
COM3). - Tap Connect.
If successful, you’ll see live data streaming in seconds!
Bonus Tip: Clean Up Unused Ports
Windows never forgets a paired Bluetooth device—even years later. If you see 10 COM ports and don’t know which is which:
- Open Device Manager.
- Right-click on old “Standard Serial over Bluetooth” entries.
- Select Uninstall Device.
- Re-pair your dongle to start fresh.
In Conclusion
OBDAI is designed to work with every type of ELM327 adapter—whether it’s a $3 white-label from overseas or a $60 professional-grade tool. While BLE is our preferred standard due to cross-platform compatibility, we recognize that Classic Bluetooth dongles are still in circulation—especially abroad and in bargain bundles.
So we’re adapting.
Windows supports Classic Bluetooth right now via serial COM ports.
Android support is on the way.
And iOS… well, Apple’s rules are what they are.
If you’re a Windows user with a Classic adapter, you’re in luck—it works great. Just pair, find the right COM port, and plug into OBDAI.
