Diagnostic VDI, VNCI, MDI with MG4

I can’t switch the car on - whole thing is dead. Currently have positive terminal off the battery in hope it resets itself. So strange tho the car just switched itself off midway through
Stupid question because you’ve probably already tried, but just to confirm, have you checked if SIPS recognizes the car even in this state?
 
Stupid question because you’ve probably already tried, but just to confirm, have you checked if SIPS recognizes the car even in this state?
Nope. No longer recognises the car. Nothings lit up. Just went back out to put the terminals back on. Still nothing but there is still power in the battery. Anyone have any idea what could’ve happened? And whether it is bricked
 
Nope. No longer recognises the car. Nothings lit up. Just went back out to put the terminals back on. Still nothing but there is still power in the battery. Anyone have any idea what could’ve happened? And whether it is bricked
That’s not a good sign. Try taking a look at this manual:MG4 guided fault finding symptom based. There are various procedures to identify and fix faults.
 
I have come to the conclusion that I have bricked my BCM. The car stopped when I was reprogramming the BCM and now that the car now won’t turn on, it points towards BCM. Anyone know how to bring the car back to life so I can attempt the work again??
 
I already had a breakdown in mid-update... by restarting the SIPS connection I or up-date the gateway and everything is back to normal.

when I planted it it was the Christmas tree on the driver's screen...
 
I have come to the conclusion that I have bricked my BCM. The car stopped when I was reprogramming the BCM and now that the car now won’t turn on, it points towards BCM. Anyone know how to bring the car back to life so I can attempt the work again??
Completely theorising… I’m wondering if the lack of BCU affects the car knowing when a bum is on the seat etc (I’d have thought the remote may awaken things but pass).

My time has ran out so can’t look but does VDS see anything as I believe it can force outputs if it can talk to modules - obv bcm may be inoperable but you may be able to wake enough up to get it going again ?
 
I have come to the conclusion that I have bricked my BCM. The car stopped when I was reprogramming the BCM and now that the car now won’t turn on, it points towards BCM. Anyone know how to bring the car back to life so I can attempt the work again??
so i’m asking questions about this situation to a chatbot that I trained with all manual of the MG4. The answer is to try if the VDS program can connect to the car and check the if the bcm is responsive. If it’s responsive and the car can’t be turned on probably it’s because the bcm is in factory or transport mode, with VDS should be possible to change the power status of the bcm. If the vds can’t connect or the vds connect but with bcm unresponsive a replacement is needed.
 
I had issues with the FVCM Module while updating with SIPS and i had to use replace function to get it working again. Think i had tried a dozen Times and it failled in between with No logical explanation. Finally it did Work and Just needed recalibration. IPK is still Open for me. Thanks to @haloweenhamster Info I kept trying.
I assume that something in the car either goes to sleep or blocks the Bus.
Also not sure If the VNCI that i had used is slower than the original part and it times out.
For BMC i have No Idea how to recover from the state, could be possible to contact the dealer to tow you in. Or do you think of BCM, that would be body control Module, that may coordinate the Basic functionality of the car. To be honest i wouldn't say a word about self updating, I assume they can figure out through SIPS logfiles, but this situation should not occur to be honest. That the car Turns off during the Update is normal, it came Back after updating. Hope you didn't Panic in this state and disconnected the Battery.
Edit: My bad you already stated its BCM, Sorry
 
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I had a charger on and it’s reading 12.8v on the battery. SIPS was saying the battery was low before the car just stopped working? There still seems to be energy in the battery though?

When it says battery low it shuts down even mid programming

12.8V isn't charging voltage, suspect although charger was connected there was a bad connection so wasn't actually working and the battery dropped below the threshold

Should be approx. 14V

I'll have a play later to see if there's anything I could suggest you try, just finished a night shift so going to get some sleep first

Hopefully get you back up and running soon
 
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Okay so I can’t do anything on VDS other than clear DTCs and programming is greyed out as I’d assume you need the car to be on for that - let me know if anyone has any ideas?
 
Okay so I can’t do anything on VDS other than clear DTCs and programming is greyed out as I’d assume you need the car to be on for that - let me know if anyone has any ideas?
So the vds can connect and read the car information? If yes can you upload the file generated by the vds after the first reading and check if the BCM have communication, so, if is it displayed as red or green?
 
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So the vds can connect and read the car information? If yes can you upload the file generated by the vds after the first reading and check if the BCM have communication, so, if is it displayed as red or green?
I seemed to connect earlier but now it won’t even let me do that
 
I seemed to connect earlier but now it won’t even let me do that
Ok, sorry, I had understood that the VDS was connected even while the car was in this state.

Even if they may seem quite useless, you could try a few tests to determine whether the BCM is in a locked state or if it has failed.

  • Try charging the 12V battery, making sure that during charging it reaches at least 13.6V-13.8V.
  • Connect the VDI only to the OBD port and check if it receives power from the car.
  • Another procedure that comes to mind is isolating the power supply to ensure the BCM is completely without power:
  1. Disconnect the 12V battery.
  2. Remove the plastic cover from the hood by unscrewing the clips holding it in place.
  3. Near the battery, you should see an orange jumper—disconnect it.
  4. Leave the car in this state for 10-15 minutes.
  5. Reconnect everything in reverse order to restart the system.
Screenshot 2025-02-16 095617.png

Ignore the TEL00052 it's only a cap to protect the connector.
 
Struggling to share it on here as it only allows images - I have communication with the BCM - alot of the fault codes relate to 'invalid data from this module'

Oh wait - here it is
 

Attachments

perfect, I'll give it a look

Only this file the vds generated? When I connect the vds the program generate a file called VDS Report with all module information, dtc and the freeze live data frame for all dtc.

Here we can see that the BCM has communication, but in the SDM (sensing and diagnostic module) there is a strange Active DTC: B193A explained in Crash out short to ground or open, according to the manual this DTC can indicate that the car think to had a crash. The other DTC seems pretty normal, I had this dtc stored always in my car and works perfectly.

Did you try to reconnect the sips?
 
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Theres the vds report

So I gave a look at the report and confronted to mine vds report. The data showed are pretty similar, so in some way the bcm work, can you do a screenshot or a report of the bcm live data section in the VDS. You have to click on the bcm in the graphics, then go to live data, click the triple arrow to the right and click start to load the data, then or do some screenshot, or in the top there is a button to print a report.
 
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