207 Non start with non ECU communication

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cdjmartin
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Joined: 22 Apr 2021, 12:33
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Re: 207 Non start with non ECU communication

Post by cdjmartin »

I should add that when I reconnect the black plug on the BSM I can't hear the relays clicking. Which is making think that the ECU is not grounding pin 9.

dfabrici
Donor 2021
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Joined: 17 Apr 2021, 23:59
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Re: 207 Non start with non ECU communication

Post by dfabrici »

Hi, nice to hear.
Definitely a ground issue from the ECU imho. Pin E1 is the main power supply enable, no wonder you have no start and no comm. Try starting and communicating with that pin grounded. If I were you, I'd open the ECU and take a look inside, to find how that pin is signalled to ground. Remember that you can't just plug the ECU and play, you have to reprogram the EEPROM with your immo code and then with diagbox you must make sure that all the other option as set as they should (alternator, a/c, gearbox, blah blah blah...). So before taking the effort of swapping the ECUs I'd have a try at repairing the one you've. That applies only if you have a bit of knowledge in electronics (but you need to have it anyway to swap ECUs and reprogram the eeprom...)

Bye
Davide

cdjmartin
Posts: 13
Joined: 22 Apr 2021, 12:33
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Re: 207 Non start with non ECU communication

Post by cdjmartin »

I've just tried start and communicate with the ECU with a manual ground running to the grey wire, I can hear the relay clicking but still no comms or crank.

Sounds like getting the replacement ECU was a waste of time as I have no idea how to go through the process you have mentioned.

dfabrici
Donor 2021
Posts: 51
Joined: 17 Apr 2021, 23:59
x 9

Re: 207 Non start with non ECU communication

Post by dfabrici »

Well not a total waste of time, as with the replacement ECU, if it has the same numbers on the label, it will definitely crank but not start, so at least that will let you know you ECU is at fault. You have then to find someone with the knowledge to reprogram the eeprom with your immo pin, or swap the eeprom chip altogether. I'd help you, but as it happens I'm a bit far :-D
Try opening up the ECU and take a look inside. They're often sealed, so pay EXTREME attention when forcing the cover open, if a screwdriver slips in it may destroy the pcb. You can find some videos on how to open it.

Bye
Davide

dfabrici
Donor 2021
Posts: 51
Joined: 17 Apr 2021, 23:59
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Re: 207 Non start with non ECU communication

Post by dfabrici »

With the manual ground, do the voltages go up ok?

cdjmartin
Posts: 13
Joined: 22 Apr 2021, 12:33
x 3

Re: 207 Non start with non ECU communication

Post by cdjmartin »

I am assuming that the voltages are ok as I can hear the relays clicking, but I haven't actually checked, I will do this this afternoon. I'll also see if I can get in to the ECU, there could well be other grounds that are not being switched.

Good point about the ECU, at least it will confirm that the current ECU is the main source of the problem.

Once again thank you for the responses and help on this, it is very much appreciated.

cdjmartin
Posts: 13
Joined: 22 Apr 2021, 12:33
x 3

Re: 207 Non start with non ECU communication

Post by cdjmartin »

Update:-

The car cranks with the new ECU! Progress!

I now have two options, fix the old ECU or get the new one programmed. Now that I also have the second option I have the confidence to take a part the original ECU to see if there is an obvious fault that I can fix, I'm hoping for a corroded soldered joint or something, but I think I'll be lucky if it is as simple as this.

dfabrici
Donor 2021
Posts: 51
Joined: 17 Apr 2021, 23:59
x 9

Re: 207 Non start with non ECU communication

Post by dfabrici »

Great news! If I had been you, I would have already cracked open the old ECU to see what lurks inside! You have to open both of them anyway to be able to program the immo pin code in the eeprom, since you have to read it from the original one (or you have to open the bsi to get it from there).
Surely, though, you need good soldering skills and a 25 series SPI programmer.

cdjmartin
Posts: 13
Joined: 22 Apr 2021, 12:33
x 3

Re: 207 Non start with non ECU communication

Post by cdjmartin »

Another update on this one - a local mobile auto electrician was able to complete the programming for me, he took away both ECU's and did what needed doing, I now have a fully running 207 with no fault codes.