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Honda didn't make any OBD2 compliant ECMs until 2016. Until then, everything used proprietary software running off laptop. You won't find any dealer-mechanics using bluetooth or phone interfaces.
 

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Here's info I have so far:

- DLC hardware interface uses ISO-9141-2, so your DLC to OBD2 adapter works, can replace bluetooth connection with USB-to-OBD2 cable. This should send K-line through to serial terminal of USB. Or you can make your own USB-to-DLC adapter shown in circuit below. Get DLC connector here: Sumitomo MT Sealed Motorsport Motorcycle Connectors - Corsa Technic

- communications occurs at 10400 baud, very slow. Downloading 256kb ECU maps will take 18-minutes.


I sent you link to MCU software. At least their read-only application will show run-time stats (live data) from ECU for diagnostics & troubleshooting. Refresh-rate may be slow due to slow link. As for flashing ECU, you first modify downloaded BIN maps, then re-flash image back to ECU using HondaFlasher.

Other than Honda's proprietary software, I'm not aware of any way to do "live" adjustments to ECU. Although I suspect it too downloads BIN maps, modifies them, then re-upload back to ECU. It's just more convenient all-in-one application rather than requiring use of separate flasher and editing software.

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According to the Chinese manufacturer's statements in the OBD2 devices that I bought there is a protocol 9141-2, and they both didn't work, the two devices ware unable to contact the ECM!
You have to separate the hardware from software. When you said "unable to contact the ECM", that is purely software issue since your phone doesn't speak same language as ECU. Hardware is connected properly.

It's like lamp plugged into wall, hardware is OK. But if power isn't sent through wires, lamp does not light. Nothing wrong with hardware.

At this point, you have everything needed to dowload BIN maps from ECU. Just need to use Windows laptop, connect to bluetooth adapter, and run the HondaFlasher software.

Or get USB-to-OBD2 adapter for laptop: 2.56US $ 20% OFF|OBD2 Car USB Interface with CH340 Chip for VAG KKL 409 OBD 2 Professional Diagnostic Cable for VAG409 KKL Car Scanner Adapter|Car Diagnostic Cables & Connectors| - AliExpress

Magic step is running HondaFlasher programme. It uses proper language to talk to ECU.

Or you write your own software. Here's guide to K-line protocols: K-Line Communication Description - V3 0 | PDF | Communications Protocols | Telecommunications
 

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Yes is purely software issue.
& No. phone doesn't speak with the ECM. The speak with the ECM is performed only between the Chinese device and the ECM, and the Chinese device transmits decoded data to the mobile.
The ECM reading software is burned into the Chinese device (protocol ISO-9141-2). Bluetooth communication to mobile, it also has some standards, and with this Bluetooth communication there was no problem. In the Chinese device, according to the manufacturer's specifications, the protocol you mentioned (ISO-9141-2) is burned in to it.
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ok, we need to back up and learn what ISO-9141-2 standard is...
 

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Ok, to truly understand how this works, you need to understand 7-layers of OSI model. You are getting "OBD2" transport-layer mixed up with "application". OBD2 just provides buckets to carry data across from ECU to application on top. What you put in that bucket makes HUGE difference. Just because 2 sides agree on using 2-liter wooden-buckets to transport information doesn't mean they will understand each other. An application must speak exact same language as devices on other side Torque speaks different language than HondaFlasher, even though they are both applications at top layer on top of OBD2 transport on top of ISO-9141-2 datalink.


Think of layer-1 wires up to OBD2 transport layer-4 as "newspaper paper". It can be yellow, blue, pink, etc. So Honda has standardised on papyrus paper (layer-1) as it's transport mechanism with blue dye (layer-4 ISO-9141-2/OBD2). IF you ALSO use blue papyrus paper, you too can communicate with Honda ECU.

However, if you pass blank blue pieces of paper through port-hole to ECU, it won't know what you're saying and it'll pass nonsense blank blue pieces of paper back. You need to add additional layers of information on top using common language. Some kind of writing or print on that blank blue paper. "Language" used at application-layer on top is what you're missing right now. Torque is writing Polish onto same pieces of blue papyrus paper being passed to ECU. But ECU only understands Japanese language written on same blue pieces of paper. That's language HondaFlasher.exe sends to ECU, no other application speaks that language!
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Underlying hardware and signaling standard is same. For example, using wire that conducts electricity. Digital TTL triggers using 0-12v pulses. Initiate communications with 70ms low, then 120ms high signal. All standardised because OBD2 uses same signals as ISO-9141-2. Since OBD2 is newer standard, it incorporates backwards hardware compatibility with earlier K-line and includes it in connector.

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Problem is app for those devices are not compatible with ECM because they use OBD2 language.
Simple.
Only Honda app will talk to ECM using K-line language.
 
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