NefMoto

Hey guys,

I am having trouble getting a 4Z7907551AA ME7.1.1 ECU from a '04 A6 2.7t into bootmode. I am using a bench harness (configured as described in the many bench harness posts on here) and a pyramid PS-3KX power supply (13.8VDC) that works with VCDS, K+Can Commander, ME7EEPROM tool, Galletto, etc so I know the harness is OK. I am able to get other ME7.1 ECUs into bootmode, 4B0907551L for example, so I know my process is OK, I just cannot get this particular ME7.1.1 ecu into bootmode.

Cables I am working with are:
VCDS hex+can (only seems to be good for VCDS)
Galletto 1260 (works great for bootmode read of ME7.1)
MPPS V13 (have not really used this one yet)
Vag KKL with a CH341 chip (paper weight)
2x Vag KKL with FT232r chip (on order)

I have come across multiple posts on boot mode issues with ME7.1.1 ECUs; there appears to be 2 flavours. Type 1 with the ST10 chip & type 2 with the Infineon chip. The ECU I am fighting with is the type 2.

ME7.1.1 type 1:
http://i41.tinypic.com/28ribtz.jpg (http://i41.tinypic.com/28ribtz.jpg)

ME7.1.1 type 2 (what mine looks like):
http://wiki.obdtuning.com/images/4/40/AUDI_ME_7_1_1_40MHz_typ2.jpg

This is what I have:
http://i66.tinypic.com/2q8a3gn.jpg
http://i68.tinypic.com/2j2vx37.jpg

I have tried grounding the boot pin directly on the flash as well as the boot pin at the bottom right corner of the Infineon chip with no luck. My process is applying power to pin 21 and 62 of the ECU, then connecting the boot pin to ground, then turning on ignition power (harness pin 3), holding boot pin to ground for various amounts of time and releasing. I have tried holding the ground for 2, 3, 5, 7, 10, 15, 20, 30 seconds. No joy. This process works seamlessly on ME7.1 ECUs (5 sec for ground). I have also tried applying power to all 3 harness connections (3, 21, 62) at the same time while holding boot pin to ground with no luck as well. I have tried the english version of Galletto, Nefmoto as well as the ME7EEPROM tool to check for boot mode status. No joy.

I have not experimented with removing components from the board or adding external resistors to the board or my bench harness. Mostly because I don't have any resistors to play with and secondly I have not come across any confirmed repeatable methods for doing so. I would like to see a known method for this particular ECU before I start experimenting and possibly ruin the ECU.


Other posts on this issue:
http://nefariousmotorsports.com/forum/index.php?topic=115.0
http://nefariousmotorsports.com/forum/index.php?topic=8563.0
http://nefariousmotorsports.com/forum/index.php?topic=4821.0
http://nefariousmotorsports.com/forum/index.php?topic=11160.0
http://nefariousmotorsports.com/forum/index.php?topic=11073.0

This ECU, actually the flash on this ECU, AA, is known to be problematic when working with Nefmoto (P1681 programming not finished). I am not sure if this is contributing to my boot mode troubles or not.
http://nefariousmotorsports.com/forum/index.php?topic=981.0
http://nefariousmotorsports.com/forum/index.php?topic=6719.0

Annnnnnnd...sure enough right after I post this I try again for the millionth time and it works lol.

No resistors added to harness.
No resistors removed from board.
The trick is power to ecu pin 3, 21 & 62 simultaneously (no ignition simulation) while ground the boot pin for exactly THREE seconds. 1 second less or more and it seems to just freeze up.

I really appreciate the excellent write-up.  Just the details of how you typically get into bootmode are hard to come by in any sort of organized list. 

Thanks for the excellent summary, and also the update.


P1681 should NOT interfere with bootmode; however, reflashing via bootmode alone will usually not clear the DTC.