Help! Bricked CEM, possibly other modules Topic is solved

[leapdragon]

@vtl Woah, that last one is not a bad idea, I'll give it a try

[vtl]

I found one dump with 24F800 in its name that I've got from somewhere like 5 years ago. VIN found in the dump is either illegal VIN or decodes as 2000 Chevy Silverado So, I'd say, I have no brick-shaped CEM dumps.

But try to reload your CEM with DiCE disconnect first, I hope it will work.

[leapdragon]

So, pulling cable from car, then exiting advanced tab, then re-attaching cable helped somewhat. It doesn't work every time, sometimes it clearly exits programming mode when I plug in, but sometimes it doesn't.

When it doesn't exit and stays in programming mode, I can now get the flash to go farther--rather than failing at 5% (Checking wake up patterns), we get through that, and through Reading customer configuration, all the way to "Status checking" 15%, at which point it ends with a communication fault.

In the logs this failuire saus it fails at VehicleStatus, SWDL_Error: 300.

I've tried a few times but we always fail at that step. :-/

[leapdragon]

The only question I still have is does the ability to flash the CEM from Volvo rely on any other module?

- The problem arose during a failed Total Upgrade CAN (timed out at ECU 40 which is I believe CEM)
- CEM is offline and several modules that we think depend on it are offline

However, my most recent attempts have been to flash just the CEM update and/or just the CEM reload. I have not yet re-purchased the Total Upgrade CAN and tried to run that again. But I'm getting a little nervous at Volvo's willingness to keep refunding software purchases and Total Upgrade CAN is again nearly $100 to try again (you can only have one software update queued at a time to try).

I have already tried Total Upgrade CAN again, but not since trying vtl's remove/reconnect cable trick, which seems to have got us a little farther, but we're failing on "communications failure" at the Status check stage, which under the hood is some error code 300.

I'm doubting it makes a difference, but if someone things "oh of course, you need to run Total Upgrade CAN again, there's no way CEM SW P/Ns will work if they're not what initially failed" then please let me know.

I'm basically at the stage where I just don't have enough knowledge or experience with the platform to know what's reasonable.

[vtl]

Flashing CEM does not rely on any other module.

CEM reload is supposed to fix the problem, since Volvo HQ knows what needs to be in your CEM (car config) by your VIN.

You have to call VIDA tech support afterwards and reclaim money they stole. In my case it was around $1k lost in all the attempts dancing around broken VIDA... This was the final nail in Volvo's coffin to me, I have no business with Volvo anymore, besides sitting on their parts hook.

[leapdragon]

SUCCESS

I wish I could say exactly what was "the difference..." but I honestly don't know.

I think your suggestion yesterday @vtl to pull the cable before closing the advanced dialog to remain in programming mode was the first key. Before that, it was just erroring out immediately, over and over again with every P/N I tried.

But I still failed with that yesterday—it got farther before failing so that at least it was trying to do things, but then it would generate that communication error. So this morning I decided to make a final attempt:

- I installed a fresh VIDA in a Windows 11 VM on a *fast* laptop instead of the older Windows 10 laptop I have set aside for VIDA live
- I made one last SW purchase, CEM reload 9438273, figuring that maybe the others that I was trying yesterday (CEM update, configuration test, total upgrade CAN again) were erroring out with a communication error because they wanted to see a CEM responding, but a CEM reload was designed for a blank CEM so shouldn't have any dependencies

It failed a couple times in a row, but it's hard to tell if it's because the CEM fell out of programming mode. It's not as simple as off/on, it seems that there's a "completely dark" state, a state with check engine light but no interior lights, a state with both check engine light and full interior lights, and a state where the cabin fan is on (?!) for some reason. So you put it in programming mode, pull the cable, close the advanced tab, reconnect the cable, and see how many things come back on each time as you plug in.

I was getting ready to give up again and just throw my hands up, but had one or two more tries in me... And what do you know, at some point the CEM reload just went in. Asked if it was a new CEM, I said no. And boom, CEM back online.

And, ironically, the VM immediately stopped being able to talk to VIDA. I was super worried at first because while DIM was back and the car could start, I still had red traingle, check engine light, and VIDA was reporting a complete inability to talk to the vehicle. I was thinking "F*@#$* something finally worked but I've written the wrong CEM payload and now it's not playing properly with the network somehow" and I spent an hour restarting the VM, plugging and unplugging the DiCE unit, and turning the car off and on.

Then I thought what the hell, I'll go back to the Windows 10 laptop and—it read the vehicle no problem, and all the codes were about the CEM being drunk. I reset all DTC codes and none came back. All is well.

So what do I take from this?

- VIDA and CAN are basically black magic, and not in a good way
- VIDA is unstable and buggy, even the latest versions on Windows 11 (i.e. the machine I successfully restored with now can't get a readout)
- My question of "which P/Ns are theoretically supposed to work in a situation like this" has an answer: CEM reload, at least, is right
- Re-learning the hard lesson: if it ain't broke, don't fix it, and don't @#*$ around with VIDA software updates unless you REALLY mean it
- I no longer have any interest in upgrading any of the remaining un-upgraded modules
- Maybe I should generate dumps of my CEMs just to have them around...

Thanks to *everyone* who weighed in here!

[vtl]

One last VIDA session: read that TCM update software number =)

[leapdragon]

Ahahaha sorry vtl, so much drama for me I totally forgot.

Is this what you need?

[vtl]

Yes, thank you!

[dikidera]

I cannot believe the 2025 vida is buggy. My custom tools seem to fare better.