Audi A4 B8 8K5, BCM2 problem and BCM2 swap

[RC300]

Hi,


I have a BCM2 with electrical problem (related to ignition relay management, but digital works fine as engine starts), 8K0907064DP with Nec 70F3381 and 95320.
I have sourced a donor BCM2 with exactly same part number 8K0907064DP (manufacturing date is just 1 month ahead).
The electrical problem disappears with this donor BCM2.


I have dumped both 95320 (files attached).


What is the procedure to swap with the donor ?
What is the material to read the 70F3381 ? Would Orange5 v1.36 be ok ? (I have no material for such at the moment)
Can someone help me to extract, adapt and transfer the files ?


With my tests, I have already lost the door open/close by remote and ESP is in test mode (ESP led on on cluster but ABS led off).
Engine still starts with the original BCM2.

[rafal]

https://www.digital-kaos.co.uk/forums/showthread.php/555749-BCM2-replaced-how-to-reassign-old-keys

[RC300]

Sorry I'm lost.
To give it a try I have transferred the 95320 from original to donor and installed donor in the car, car does not start but the original electric problem is solved.
As expected, VIN exposed by BCM2 is cabalistic characters and ESP module reports VIN does not match (logic btw), so I assume the 70F3381 code flash needs to be transferred from original to donor.
I miss the additional steps to make the donor BCM2 working.

I remind I try to be in the best scenario: I have two BCM2, original and donor are the same part # 8K0907064DP

[Antonio266]

You have to write both NEC MCU and Eeprom data from Original to donor BCM

[RC300]

As I try to repair the car for a friend, I cannot invest hundreds of euros (it's one time repair).
I have Audi S4 B5 (immo cluster) and all this BCM2 world is new to me.

Which tool can read/write Nec 70F3381 seamlessly ?
Any risk about Component Protection ?

[Antonio266]

If you have no experience in reading MCUs and you don't know how Immo system works on Audi BCM2 platform let do the job to someone else, you could easily mess up the car and then will not start again.
For r/w NEC mcu you need something like VVDI Prog, XProg or UPA-S, all genuine, no china tools..

[RC300]

I have experience with my Audi S4 B5.

Orange5 can r/w Nec 70F3381 ?

What about the Nec serial HW number , code flash is linked to it, right ?
I suppose its not a simple clone operation or is it ? Read original code flash and write it in the donor !?

[Antonio266]

Honestly i don't know if Orange5 clone will r/w that MCU, genuine will do it for sure..
If the two BCM are exactly same Part numbers a full clone with programmer will work, if they are different you will need to move immo data

[ollync]

Or replace both eeprom and mcu


Sent from my iPhone using Tapatalk Pro

[RC300]

Xprog v6.12 ?

[RC300]

Or replace both eeprom and mcu



TQFP package is not easy to desolder/solder, even with warm airflow. I noticed the PCB is not high quality neither.

[RC300]

Any link for the pinout between BCM2 and Orange5 ?
Is the XTAL on the board used or Orange5 provides the clock ?

[RC300]

Well, I collected all the info. about the wiring.
On BCM2 using 95320, the data flash of 70F3381 is not used at all !?
Or is the data flash read and needs to be cloned too ? What is the content/purpose of data flash for BCM2 using external EEPROM ?
Why is the 95320 content screwed up when the Nec code flash is not the right one ? (I read back the 95320 on-baord and 630 bytes are different compared to the ORIGINAL dump I wrote off-board).
Is it delibarate from the firmware ?

[RC300]

Thanks to all,

I succeeded in cloning the BCM2:
Nec 70F3381 code read and programmed with iprog+ (Data flash is all 0xFF)
95020 read and programmed with standard EEPROM programmed

Outcome: only few digits @7FA4 differ between the Nec firmwares