Konwei KDIAG is the cheapest Bi-Directional scanner I have ever found so far. It might not have the best vehicle & function coverage for advanced functionality but it does already work with 30+ brands and even offers bi-directional tests for not only cheaper price for adapter, but also without any yearly payments. Updates are free for KDIAG.
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Konwei KDIAG is not the best bi-directional scanner but given it’s low price and free updates, it is even cheaper than most engine code readers or ELM327 adapters.
And it comes with features they do not have, like full scan or bi-directional testing.
Find the best price
Who tested product & wrote this review?
Tester & Editor for this review: Juraj Lukacko
Hello, I am Juraj (Yuri) and I tested this product to help you decide if it is something you would want to buy, and if yes, show you how to use it.
I make honest reviews based on personal testing in my own garage and If I see the product is bad, I will make it very clear in review.
Read more about how I do reviews on Iamcarhacker.com in my review policy.
Reviews from the community
I had one person from the email community reach out to me with his review of Konwei KDIAG (he wants to remain anonymous):
Review from the community:
An update Yuri
YES, this is indeed a useful miniature “ädvanced” car scanner, a step up from a basic OBD scanner, looking at ECU and TCM.
I believe as more people like you and I get more involved with the care of their cars, this type of connector will become more of the standard.
Sometime ago my car sat in 1.5 ft of water for a few days. The water entered the car but not up to the gas pedal and it was below the spark plugs.
The car could start, but the electronic hand brake couldn’t release.
I also had MANY lights in my dashboard
- EyeSight off
- Collision detection and lane departure detection off
- Traction control off
- ABS error
- Handbrake sign flashing
- Electric steering wheel alignment error
- Hill take off assist off
- Vehicle occupant sensor off
There’s a procedure to release the handbrake manually, and I drove the car somewhere safe to dry out
The KDIAG helped me reset some parameters in the various other systems.
- Clear ABS error after cleaning the brakes with carb cleaner. I could see that on one of the wheels the mud was interfering with the sensor
- I reset the centre position for the electric steering
- Set new idle rpm at 680
- Also did a throttle range relearn
- Cleared all stored historical error codes.
There’s access to other systems like the car fob remote, automatic wiper function.
There’s even an option for a google search for info on error codes.
For now I’ll keep on exploring. The app is useful but CLUNKY and CRUDE.
If they redesign it this scanner could really shine.
I bought his scanner after seeing your mini review – Thanks for your work. 
Konwei KDIAG is the cheapest Bi-Directional scanner
It might not have the biggest vehicle coverage, but if it supports common brands you work with you might give it a shot.
Definitely cheaper than one of the bi-directional scan tools.
I tested a lot of different Bluetooth OBD scanners
I tested more than 30 different Bluetooth OBD scanners, so the review is crafted based on the level of value it can give you for money spent. Here is a list of the Best Bluetooth OBD scanners.
Features
| Feature | Verdict |
|---|---|
| Connection Type | Bluetooth |
| Device type | Bluetooth adapter |
| Need extra device | Smartphone (Android, iOS) |
| Need internet | For updates |
| Own software | Yes |
| Can use 3rd party software | No |
| Subscription/Update | FREE Updates |
| Vehicle coverage | 40+ brands |
| Global OBD Modes | Yes |
| Live data graphs | Yes |
| Data logging | NO |
| Scan other modules | Yes |
| Diagnostic report PDF | Yes (very simple looking) |
| Full live data | Yes |
| Bi-Directional | Yes |
| Service Procedures | 4 |
| ECU coding | NO |
| Full review + video | https://www.iamcarhacker.com/konwei-kdiag/ |
| Price range | $0-50 |
| Current price | https://amzn.to/434DnSr |
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Hi, I am Juraj “Yuri” Lukacko. I got frustrated by unhelpful and scammy mechanics, so I decided to learn everything about car diagnostics myself. I test dozens of new car diagnostic tools every month along with learning new strategies to fix and customize cars. About Juraj Lukacko (Yuri)