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Re: PCM replacement

Posted: 14 May 2021, 11:53
by Syntax
I can try it with the AG91-12B684-DA but the AG91-14C273-AA is the one UCDS wanted to download.
My notebook has only one USB functional and even though I dont know right now how to connect 2 OBD cables at the same time. I would have to create some kind of split cables and manually pin them to car and those cables one by one right?

The reading through Kess finished successfuly so I guess thats all I have.

Could you please help me in installing the new PCM to the car? I really need the car to be functional and the old PCM does not want to be raised from the dead as it seems :D

Re: PCM replacement

Posted: 14 May 2021, 12:28
by DGAlexandru
You can have UCDS connected to OBD port and ELM connected with only 4 wires: HS CAN High and Low, +12V and GND - to the wires going to the original OBD port.
.. or use something like this: https://www.alibaba.com/product-detail/ ... 89836.html - I have one with 1 male and 3 females :)

Re: PCM replacement

Posted: 14 May 2021, 12:36
by Syntax
Ok thanks for the info, I have been looking at those splitter now.
But as I said my laptop has one one USB functional so I would need another one.
What would happen if the PCM would be still communicating or not? What would be next steps?

Which vbf I should upload to the new PCM so it has the correct software?
Also how to do the PATS step by step and the Incode calculation (I have access to this site http://autokeyprog.com/service.php?id=pats_calc and also have TM100 installed)

Re: PCM replacement

Posted: 14 May 2021, 14:02
by DGAlexandru
For BG91-12A650-R* you need BG91-14C204-D*

AutoKeyProg can't be used for the newer Fords.. mainly every model that was launched after May 2010 has a new PATS algorithm... for Europe at least.
If it is Euro4 or less, then old PATS algo; if it is Euro 6 or higher then new PATS algo.
Almost all Euro5 models have new PATS algo, but there are some like Focus 2 / Kuga 1 / C-Max 1 that even if they have Euro5 engines, they still have old type PATS algo.

Re: PCM replacement

Posted: 14 May 2021, 14:18
by DGAlexandru
If the old PCM still replies over CAN then it can be repaired... but you first need to understand those messages in order to know what sequence it requires in order to be able to upload the SBL to it.

PCM is like a Personal Computer:
it has a small software that acts as a BIOS; this software is very rarely touched by OBD software update.
at booting process if you're sending the right message over CAN it will stop loading its "running" software from flash and will wait for a SBL instead to be loaded from CAN; the required messages are sent by UCDS in "dead module" mode; IDS has an automated process that checks for this stage.
if the "running" software in PCM is good, then other CAN messages will instruct PCM to load the same SBL
after the SBL is loaded, PCM is in flash programming mode and now you can put the needed "running" software

The "running" software can be only one "block of software" or it can be divided in more parts: "operating" software, "maps data", "database", "CAN signaling" and so on. Depending on the type of flash and the way the "running" software is designed you can instruct it to erase and write only a certain part of the flash.

There are PCMs that have the "BIOS" on the same flash chip as the "running" software so they can be bricked if the SBL allows the "BIOS" flash contents to be touched and the flash process is wrong.

Re: PCM replacement

Posted: 05 Jun 2021, 00:49
by paxtonix
Syntax wrote: 13 May 2021, 06:38 Hello, does anyone know if the PCM can be easily replaced by another hw version or it must be strictly the same?
By easily I mean plug and play and then some vbf loading with UCDS (I have chinese one) or initialization through Forscan.
My PCM is BG91-12A650-RC (2011 85kw manual trans) and I do not have keyless.
I didn't go thru all thread, but I give you some basic info

Siemens/Continental/VDO - SID 206 ( Ford Mondeo 2.o TDCI DW10 Engine 2007-2010)
DELPHI - DCM 3,5 ( Ford Mondeo 2.o TDCI DW10C Engine 2010-2014)
BOSCH - EDC 17Cxx ( Ford Mondeo 2.2 TDCI DW12 and DW12C Engines 2008-2014)

About ECU SW and HW - in preFL models - that acctualy play no role. in MidFL and FL cars it does. I will focus only on fl models cuz this thread is about it.

DCM 3.5 can be divided by 2 HW , Only last part of number plays a role. First is an module with 4*5*2 symbol like ( xxxx-xxxxx-xx) , second one is with 4*5*3 symbol like xxxx-xxxxx-xxx.

DCM 3,5 with 2 symbols on end is an ECU for a car equipped with 1 lambda probe for Diesel Particel Filter. DCM3,5 With 3 symbols on the end is for a car equiped with 3 DPF lambda probes. So it take us to SW part. If ecu will be cross flashed by a file from xxxx-xxxxx-xx, in ecu with xxxx-xxxxx-xxx and other way around, it will kill your ECU. - But it can be recovered any way so don;t worry. Just need right tool.

Now about Immobilizer. If your trying to fit ECU from other car. Unfortunately you cannot pair a DCM3,5 ecu with forscan and any available software out there. - reason why is because from 2010 Ford have moved from PATS to iPATS - what means that you need a connection to ford online database ( FDRS ) or to Ford Etis, cuz the outcode and checksum in the ECU uses RSA algorythm with a privat key out from FORD Online Server. RSA key size is 2,048 to 4,096 bit typical ,making it unpossible to brake or recalculate . Now days desktop PC need like 1,5 miliard years to break 2048 bit RSA, :lol:

Anyway- answering your question from first post, you need to have right HW ecu for your current engine, and adapting it will be bit more difficult and expensive thru connection to FDRS. So only way is Authorized Dealer to fix IMMO issue . Rest you can do by ORI UCDS or any other J2534 device connected via Ford Etis / FDRS online flasher. Or if you had ori file from your ECU, you could recover via some clone flashing tools.

Re: PCM replacement

Posted: 05 Jun 2021, 17:21
by Syntax
Thanks for your answer.
I have my car working and I am using the mentioned BG91-12A650-FGE PCM which has the BG91-14C204-DP calibration and after pairing it with the PATS at Ford service it works without problem so I guess your theory is not 100% right.

Anyway I have recovered the dead PCM by manually connecting it to UCDS cable and flashing it so I will try to place it in the car and see if it still works without pairing.

Re: PCM replacement

Posted: 06 Jun 2021, 09:10
by DGAlexandru
It will not work - now the other modules that are part of PATS know the S/N (and/or other info) of the current PCM.

Re: PCM replacement

Posted: 07 Jun 2021, 10:53
by Syntax
How does the immo off work then? Something like this https://www.youtube.com/watch?v=P1C97Y8b70c
If the other components in PATS need to know exact S/N of the PCM then there would be no way to bypass that other than copying the S/N from paired PCM to new one.

Re: PCM replacement

Posted: 08 Jun 2021, 04:22
by DGAlexandru
PCM also needs to know S/N (or something else of BCMII).
In the example above that adaptor sends over CAN a message that contains that S/N that was read from PCM's EEPROM (an ID or S/N of a module that PCM needs to read over CAN in order to think it's in the right car).

In Mondeo 4 even ABS is part of PATS.