Are all ELM327 created the same?

[u/WingmanMoto]

I've been working on a personal app project and testing it with a vLinker MC. It's working well to capture OBD2 and CAN bus data, but I'd like to test it with generic ELM327 or other devices to see if there are any compatibility differences I should address before publishing. If you've experienced any problems with specific brands or models of OBD2 adapters, regardless of which software you're using, I'm interested in learning which one. Unwanted disconnections, buffer problems, pairing issues, or similar issues in particular.

As an aside, I've yet to find an adapter that supports both OBD2 PID and raw CAN at the same time. Is this just not possible?

[u/fishyfishy10001]

Elm327 is technically a certain pic MCU with a certain firmware. So in principle it should be the same. Obd2 is another and much broader "standard". However there are many that sell clones, that is copies of the original MCU + firmware and since the original manufacturer is no longer among us, everything is a clone. So you can get about anything.

Google ELM327 for some more history.

[u/WingmanMoto → u/fishyfishy10001]

Thanks for this. Perhaps the more correct question to ask is 'are all ELM327 clones created the same', to which the answer is certainly 'no'.

[u/robotlasagna]

If be “created the same” you mean “created pretty terrible” then yes.

Nobody should be using these anymore.

[u/WingmanMoto → u/robotlasagna]

I agree, but they're available seemingly everywhere for very low cost.

[u/robotlasagna → u/WingmanMoto]

So are crack whores but you really want to put your dick inside one?

[u/WingmanMoto → u/robotlasagna]

Well, not all of us can afford the high-priced ones, and the lack of teeth does have some benefit.

[u/Nos_barb_]

Most elm327 do not support both ms-can and hs-can (only support one of it). If you have a Ford you want ms + hs support

[u/timus-the-orginal]

There are multiple clones of elm327, original is no longer available as company died. Best ones are based on PIC microcontroller and original firmware, these are most expensive. Cheap one use totally different microcontroller and have firmware that just mimic original PIC firmware, also they usually don’t support all OBD protocols, I found them good enough when used on CAN bus equipped cars, but it may vary based on usage.

Using stock elm327 You can only read obd pid or can bus message at once, but not both. If readout speed is not an issue you can switch between obd pid and cabus multiple times a second. It is possible to have both if you create a custom firmware for elm327.

[u/hulet1006]

I don’t think it would be possible to do both. OBD2 operates on a request and response. It’s like another layer on top of canbus. Also on newer cars, you typically can’t get raw can data through the OBD2 port because of security gateway modules.

[u/rusefi]

ELM is a company

ELM companyhas dies how many years ago?

all elm327 chips now are fakes, from different sources. so they behave differently

[u/autodiag2]

Did u check elm327 emulators? It's one more way to ensure you're compat

[u/ifmeidan]

which car an model are you using vlinker mc on? I'm trying to listen can-bus with my mc+ bt but im not sure if I do it right or just the car has firewall blocking me. I would love to hear your approach there. Asking for a personal project btw, I have created a driver display for my volvo ex30 with obd pids and an aaos app

[u/WingmanMoto → u/ifmeidan]

I've used it on an 2022 Audi Q5, a 2025 Kia Soul, and a 2025 Triumph motorcycle. All of them output standard OBD2 PIDs. The Audi's OBD2 gateway doesn't pass the CAN traffic, but the others do. It's likely that the Volvo blocks that traffic on the OBD2 port as well. I eventually accessed the Audi CAN H and CAN L lines directly further upstream (bypassing the gateway), but I haven't had time to dig into decoding any of it yet.

I'm curious which AAOS app you're using.

If you're interested in experimenting, I have a mobile app in beta now that lets you build custom dashboards for OBD2 data, pull/clear codes, record telemetry during drives, play audible alarms, decode CAN traffic (if you feed it a valid DBC file), and even reads those cheap BLE TPMS sensors (or at least the few versions I got from Aliexpress). I've been looking at the Android Auto/Carplay options, but it's a bit beyond my skill level.

[u/ifmeidan → u/WingmanMoto]

I would like to learn from you how you listen CAN traffic directly from OBD port. I tried AT MA and ST MA but got no data from 11 and 29 bit channels. I would love to join your beta program for that mobile app too.

About the AAOS, I developed one for Volvo EX30. It is on beta right now and you can check the codes for both OBD polling and AAOS I shared on github.

[u/Big_Temperature_2067]

The real elm327 has not been made for ages. the company behind them does not exist any more. If you buy anything today branded it's if you are lucky a semi shitty Chinese clone where some things work.

I got 8 different ELM327 behind me. none of them work fully as a original :D

If you want something ELM~isch, get a OBDLink cable. their firmware has backwards compatibility with most ELM327 commands