C3 Pluriel Electronic nightmare!!

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AllanA
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Re: C3 Pluriel Electronic nightmare!!

Post by AllanA »

oops no, ST 95160
ozvtr
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Re: C3 Pluriel Electronic nightmare!!

Post by ozvtr »

I don't know what level of experience with programing EEPROMs you have, So I'll assume you don't have any.
The cheap USB based EEPROM reader/programmers will come with basic software to read and write HEX data to and from a number of EEPROMS. Make sure the programmer reads the EEPROMs that you will be working with. You might also have to buy adapters the fit the package style of your target EEPROM.
Most of the time it's possible to read the EEPROM in circuit. However it doesn't matter if you are pulling the original EEPROM out. Typically it's easier to read them out-of-circuit anyway.
So making copies of the original data on the EEPROM is easy. Once you get your "dump" (copy) off the EEPROM, it is then processed through a program to modify that dump. The modified data is then written back onto the EEPROM using the software that came with the programmer. The programs only manipulate the data files, not the actual EEPROM. So you will always have a copy of the original dump if something goes wrong. Just don't keep renaming your files with the same name. :D
I have used the software that came with the EEPROM reader, ImmoKiller and NY04 to read and modify data in the BSI and instrument cluster. I don't know of any programs that will modify the engine PIN in the BSI.
If you know what you are looking for, you can spot the engine PIN in the BSI dump without a special program. HOWEVER, just changing what you can see wont work! There are check sums hidden in the data which stop it from being that simple.
I have not attempted to change the data in an engine ECU...yet.

As I have said before, removing the immobilizer (Immo off) is potentially fraught with problems. But if you wish to experiment, don't let me stop you. A worse case is that you have wasted your time and have to reprogram the EEPROM...no big deal. I cant say it won't work, just that it's a possibility it will do things that you don't expect.

You should make sure the part number AND REVISION of the "new" engine ECU are the same if you are swapping the whole EEPROM!!! Changes of revisions MIGHT put the data on the EEPROM in different places!!! I know this is the case for the BSI's! But as I said, I have not fiddled with with engine ECUs and NOT diesel ECUs at that! If you are going to modify the data on the EEPROMs and change the PIN, the program should guide you to the correct revision (IF APPLICABLE).
AGAIN, this step might not be needed all the data could be formatted the same way...just a heads up.

Another idea is the possibility that it's the CAN BUS controller in the engine ECU that's causing the problem. If you are prepared to desolder the EEPROM are you prepared to replace the CAN BUS controller? You may have the opportunity to repair the old ECU and have 2 that will work in your car? Just a thought. :lol:
wheeler
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Re: C3 Pluriel Electronic nightmare!!

Post by wheeler »

I take it the intention would be to read & backup the original eeprom that contains the security data then just overwrite that file onto the eeprom of the ‘new’ ecu?
Do you not think that will work? I dont think the idea is to modify any of the content's of the dump, just to completely overwrite it with a backup from the original.
AllanA
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Re: C3 Pluriel Electronic nightmare!!

Post by AllanA »

Ozvtr and wheeler, thanks for all your input and help to me. You're correct in that I am totally new to eeprom read/write but life is all about learning new things at whatever age!

My soldering skills however are pretty good. So, my intention is to desolder the eeprom from my original ecu and do a straight dump to file of the original eeprom data and save it. Then remove the eeprom from the donor ecu and overwrite it with the original eeprom data and resolder to the ecu. No changes whatsoever. Then temporarily refit the ecu and hopefully fire up the engine. Once I know it's working I'll reseal the ecu case. Job done. Yeah!!

I've also ordered some additional 95160 eeproms so I'll write to a couple of them for backup purposes.

I don't want to risk any changes to the data as the car has been off the road for long enough!! And I want to get back to making electric guitars :):)
wheeler
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Re: C3 Pluriel Electronic nightmare!!

Post by wheeler »

From my understanding this should work but im fairly new to eeprom too so i may have the wrong end of the stick.
ozvtr
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Re: C3 Pluriel Electronic nightmare!!

Post by ozvtr »

My post was just an overview of the whole process. Not necessarily everything that needs to be done.

To be honest, why not just remove the "old" EEPROM and install it into the "new" engine ECU? Don't faff around with the EEPROM programmer at all. I would be more interested in whether it's going to work or not, first. I'm impatient :-D . If it does work and you want a copy of the dump, you can try to make a copy in circuit. That will work about 90% of the time. I'm not a fan of un-soldering and re-soldering multiple times.
However, I can see why you might want to wait and get the copy first. But then again if it does work...why would you need a copy of the EEPROM?

BUT, as I said if there is a problem with the revisions of the engine ECU's, and it ("swapping" EEPROMs) doesn't work, you may be forced to modify the dump to change the PIN. Or go for the immo off option.
IMHO you need to know if swapping the EEPROMs will work, first.

Luthier huh? Prefer valve or solid state amps? Or does your interest stop at the pick ups? :lol:
AllanA
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Re: C3 Pluriel Electronic nightmare!!

Post by AllanA »

Well finally my eeprom programmer and software arrived on Friday afternoon. I bought the APU USB version 1.3 with an additional soic clip. I also ordered a nice little oscilloscope that I’ve wanted for ages and is a real boon to automotive diagnostics. A Pico 2204a running slightly adapted Pice Automotive software!

I’ll describe what I did just in case other novices are interested.

I decided to proceed with caution and used a soic8 clip to read the eeprom in situ on my original engine ecu, then saved the dump to file on my pc.

I then desoldered the eeprom from the board, placed it in the soic clip again and read the contents. Then made a comparison between the two dumps. Result was both exactly the same which confirmed no spurious info had been picked up from the in situ reading. This made me a happy lad knowing that I didn't need to do any soldering work on the donor ecu.

I read the donor eeprom, saved it and made a comparison with the original which showed significant differences.

I then programmed the original dump in situ to the donor ecu and reconnected the ecu, minus its cover just in case!

I ran Lexia and it was great to see NO faults, Went into BSI config and cleared eco mode. Then the moment of truth. I turned the ignition key and the engine immediately fired up. Sooo nice to hear after being a non runner since before Christmas.

Drove about 120 km yesterday and it performed well so my wife is very happy and I’ve scored loads of brownie points!

Finally I have to say a big thanks to all that have provided me with advice, support and vital circuit diagrams. And if I can help anybody through this process or any other C3 Pluriel issues in future just PM me, I’m happy to help.
wheeler
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Re: C3 Pluriel Electronic nightmare!!

Post by wheeler »

Excellent work, good to know that the eeprom will read & write OK in circuit.
Out of curiosity what was the mask ID of the eeprom?
AllanA
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Re: C3 Pluriel Electronic nightmare!!

Post by AllanA »

ST95160
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CitroJim
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Re: C3 Pluriel Electronic nightmare!!

Post by CitroJim »

Superb work :D
Jim

Runner, cyclist, time triallist, duathlete, Citroen AX fan and the CCC Citroenian 'From A to Z' Columnist...