Thread: Recovering a bricked NNN ecu

Originally Posted by OffTrack

It finally clicked that I had a fair bit of junk on the card that had been loaded after I did the initial remap to the LR map for an EU2 Auto. The Td5Inside map had been loaded later again, and the issue wasn't power but slow disc access. After quick trip inside to reformat the card and copy the map across the new map loaded up far faster and without any hesitation.

Lesson learned and I'll only be using freshly formatted cards in future.

Just let me get this right,

You format the SD card that goes into the Nannocom and then upload only the remap file
Then upload it to the ECU?

(I have had problems in the past with bricking the ECU and had to play to get it right)

Any thoughts on if the capacity of the card has an impact on read speed?

Originally Posted by onesilop

Just let me get this right,

You format the SD card that goes into the Nannocom and then upload only the remap file
Then upload it to the ECU?

(I have had problems in the past with bricking the ECU and had to play to get it right)

Any thoughts on if the capacity of the card has an impact on read speed?

Yes, that is pretty much it.

The only file you want on the card that goes into the Nanocom is the map file.

By reformatting, then writing the .map file first the data is written to sdcard as a contiguous stream at the start of the card. If you have other files on the card the data can be broken up into smaller chunks and it takes longer to read the data from the card.

I'm using a San Disk 8Gb card, which is something like 20Mb/s. I think it more a question of having the data cleanly written to the card. I was able to test with a stock map file that had been written to the blank card, and then the td5inside map which was written after the card had been used in a camera (it was an emergency!). The stock map consistently flashes fine, while the td5inside map failed every time. As soon as I reformatted and reloaded the td5inside map it flashed first time.

cheers
Paul

Originally Posted by OffTrack

After all the mucking about, once the new flash chips arrived it was a bit of a non-event.

What I did discover was that I probably stuffed up reflashing. I'd loaded the flash image, then erased the chip,read the chip to check it was empty, wrote the image and then verified. Which all appeared to go ok. I did the same procedure today but noticed that the write went far too quickly. When I checked the buffer was empty: the read after erase fills the buffer with the contents of the erased chip.

So the correct procedure is erase, read chip, blank check, load file, write, verify.

I'd basically resoldered a blank eeprom. Ooops.

This time I had a positive result soon as I hooked up to the D2. I was able to download the existing map, although it failed on first attempt. When I tried to upload the Td5Alive map it failed at 30%, and I was thinking that I'd be back at the soldering iron. Fortunately I think LR are smarter than Colin gives credit for, as the boot sectors are deleted only after the main body of the upload completes. The "please wait" with 10% to go appears to be the sector of the memory holding the boot loader program being deleted, and an upload failure after this point bricks the ECU.

It finally clicked that I had a fair bit of junk on the card that had been loaded after I did the initial remap to the LR map for an EU2 Auto. The Td5Inside map had been loaded later again, and the issue wasn't power but slow disc access. After quick trip inside to reformat the card and copy the map across the new map loaded up far faster and without any hesitation.

Lesson learned and I'll only be using freshly formatted cards in future.

Off to take the new map for a test.....

Thanks for your post I have asked before what is happening as I too have noticed that the bricking only happens if it fails in the last 10%.
I have trashed a couple of ECUs in my playing with the Nanocom.
Am at the point of buying a power gate as the $800 purchase will be cheaper than having ECUs repaired.
Once again thanks for the post.

Originally Posted by djam1

Thanks for your post I have asked before what is happening as I too have noticed that the bricking only happens if it fails in the last 10%.
I have trashed a couple of ECUs in my playing with the Nanocom.
Am at the point of buying a power gate as the $800 purchase will be cheaper than having ECUs repaired.
Once again thanks for the post.

There is another way to tackle the problem that is far less intrusive, and quicker to do. I'll have the bits i need next week and I'm looking for an ecu to revive. If you feel like posting one of the dead ecu's to me I'd be glad to have a test subject. You can have it back when I'm done

Sadly at this moment all 3 of my ECUs are all in a working state.
I just spent 3 Months fighting with the last repairer to get him to send it back.
I would gladly send you one but I just dont have one

No problem, it's not that critical I have access to a bricked ECU. I can test out the no-solder method on my ECU.

For the record the card I'm using is a SanDisk Ultra 8gb 20MB/s.

Originally Posted by spudboy

Well a lot of all that went over my head, but am well impressed that you got it all working in the end. Nice work

Thanks

The desolder-program-resolder method clearly works and if you don't have to jump through the hoops of getting a computer setup from scratch it's probably a reasonable option.

That said, there is another way which has been used extensively by the SAAB tuning community that should work for the NNN ECU's - and possibly for MSB ecu's that have had a eeprom fitted.

The SAAB Trionic 5 and 7 ECU's are based on the same CPU chip as used in the Td5 MSB and NNN ECU's. The Trionic 7 uses a larger version of the AMD eeprom used in the NNN ECU's.

What I've discovered is that the SAAB crew are using an old DOS program and scripts that are essentially unchanged from example scripts supplied by Motorola. At this stage it looks like it will be possible to either use the existing scripts, or worst case they will require minor modifications.

There are simple tutorials on the SAAB Tuning sites on creating bootable USB sticks which can run the DOS app so this gets around the need to have a dedicated win98 machine.

The parallel port adapter can be picked up for around $40 from ebay, or can be built DIY if you are so inclined.

The nicest thing is that by using a "pogo pin" adapter you can do the reflash without soldering on the ECU at all.

Anyway I'll expand on this in a new thread.


cheers
Paul