Nexlink ODB won't connect to ECU

[CanyonReveller]

I've got a pre-facelift MG5 from the second half of 2021 and no OBD reader seems to connect to the ECU. I found a recommendation for a Nexas Nexlink BT5 device elsewhere on the forum, which that user said works with their car. However, it doesn't seem to work for mine.

I'm using an Android phone with Car Scanner Pro. I think I've tried all of the connection profiles now, but still no dice. The phone connects to the dongle fine, but the dongle can't access the ECU. I tried torque scanner pro in case it was something to do with the app, but that didn't fix it either.

Anyone had similar problems? Any suggestions on what might be wrong?

 

[emmrecs]

Is the reader you have this one?

If so, I have one, linked to Car Scanner Pro on my Android phone without problem, on my pre-facelift MG5, bought March 2022. What likelihood, despite the fact the phone connects to the dongle, is there the dongle is faulty?

Also, have you ensured the dongle is fully inserted into the OBD socket? I always have to ensure it is fully inserted before attempting to read the data.

 

[CanyonReveller]

Is the reader you have this one?

If so, I have one, linked to Car Scanner Pro on my Android phone without problem, on my pre-facelift MG5, bought March 2022. What likelihood, despite the fact the phone connects to the dongle, is there the dongle is faulty?

Also, have you ensured the dongle is fully inserted into the OBD socket? I always have to ensure it is fully inserted before attempting to read the data.

That's the one. It seems to work fine on the mk8 Honda Civic we have, so I think the dongle is OK.

When I plug it in, it lights up with a blue flashing light, so I think it's fully inserted.

Do you know which protocol car scanner is using to communicate with the ECU? Also are you using Bluetooth, or Bluetooth LE? The app should say somewhere, hopefully.

 

[emmrecs]

Those settings seem identical to mine!

From the first screen you show, if you click on "Advanced Settings", what is shown under "ECU Protocol". Mine says "0) Automatic by ELM327". All the options you show in your second screenshot are what I see if I click on that "0) Automatic..." line but I've never needed to select anything different there.

Which version of Car Scanner Pro do you have? Settings>Info shows mine as 1.104.0, build 401040.

 

[CanyonReveller]

Thanks for checking and for your help.

My app version is the same as yours.

Some BMWs have issues with the auto ECU protocol selection, which can be fixed by selecting it manually. It may not help, but I thought it was worth a go.

The Nexlink user manual says the Bluetooth protocol used can matter too, but it seems like that isn't the issue either.

My car was serviced in December, so I assume they managed to connect to the OBD port ok.

I'm stumped!

 

[emmrecs]

Sorry to not be able to finally help to resolve this for you, but just to reassure myself I was not imagining any of this I've just been out tot my car, plugged in the scanner and immediately read the data in Car Scanner Pro!

However, I wonder what is the chance/possibility that the OBD port on your car is faulty in some way? Is there any chance you could "borrow" a different dongle, preferably one you know functions properly, and test whether it "works" in your car?

 

[CanyonReveller]

I've tried a few other OBD readers as I've got a bit of a collection going, but they're mostly older models and I've seen several people having issues with those.

At this point, I guess I'll try the other model people are having success with and see if that's any better.

Thanks again for all of your help.

 

[Gomev]

I've got a pre-facelift MG5 from the second half of 2021 and no OBD reader seems to connect to the ECU. I found a recommendation for a Nexas Nexlink BT5 device elsewhere on the forum, which that user said works with their car. However, it doesn't seem to work for mine.

I'm using an Android phone with Car Scanner Pro. I think I've tried all of the connection profiles now, but still no dice. The phone connects to the dongle fine, but the dongle can't access the ECU. I tried torque scanner pro in case it was something to do with the app, but that didn't fix it either.

Anyone had similar problems? Any suggestions on what might be wrong?

I have exactly the same problem with my 5.
No problems at all in my previous ZS EV but no OBD connects to the ECU in this one.

 

[CanyonReveller]

I have exactly the same problem with my 5.
No problems at all in my previous ZS EV but no OBD connects to the ECU in this one.

Have you tried the nexlink and vgate icar pro OBD readers that are recommended elsewhere on the forum?

 

[Gomev]

Have you tried the nexlink and vgate icar pro OBD readers that are recommended elsewhere on the forum?

I have a Vgate, my original, and then when that didn't work on my present car, I bought another that was recommended on here. That doesn't work either.
I am not going to spend money endlessly buying OBD readers. If anyone lives locally and theirs works I would be happy to meet and try theirs.
It also appears I am not the only one that for some reason cannot connect with whatever I try.

 

[MickeySw]

It also appears I am not the only one that for some reason cannot connect with whatever I try.

The obvious would be a faulty OBD port, however it could also be FW related, therefore as far as you’re aware are your ECUs on the latest revs?

 

[CanyonReveller]

As far as I can tell, I'm on the latest firmware as of the last quarter of 2023.

One of the connectors in my OBD2 port has significantly less resistance than the others to the insertion of a paperclip, so I think it might be a loose connection. It's a bugger to get full access to the port to adjust the spring tension though.

 

[MickeySw]

One of the connectors in my OBD2 port has significantly less resistance than the others to the insertion of a paperclip, so I think it might be a loose connection. It's a bugger to get full access to the port to adjust the spring tension though.

Might be worth consulting the OBD2 pinout first, not all connectors are used for communication.

 

[CanyonReveller]

Might be worth consulting the OBD2 pinout first, not all connectors are used for communication.

You're quite right, but of the 5 that are wired up, one is pretty loose.

If anyone is able to identify the ECU protocol that the MG5 uses, it'd be really helpful in speeding up fault finding.

 

[Gomev]

The obvious would be a faulty OBD port, however it could also be FW related, therefore as far as you’re aware are your ECUs on the latest revs?

Isn't that something you find out by using the OBD ?

 

[CanyonReveller]

In an ideal world, sure. I guess I just have to trust the dealer did the updates when I put her in for servicing at the end of last year. There was an outstanding safety recall for the brake lights, so hopefully they at least did the software update for that.

I can see some version information in the engineering mode on the head unit, but the OS version is still "EP22_NAVI_8in_16G_01_20210203", which does not look all too recent.

I have exactly the same problem with my 5.
No problems at all in my previous ZS EV but no OBD connects to the ECU in this one.

I've managed to connect to mine using the Roewe eRX5 profile in car scanner pro. The recommended nexlink adapter is still struggling with that profile, but the iCar Pro BLE adapter is working, can scan fault codes, and can measure the current in the AC system with variations consistent with me turning it up/down/on/off.

None of the MG5 profiles are working yet, but this seems consistent with outdated firmware.

Progress!