Vaux fails to start with another ECU

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Fri 11 Feb 2005 17:28
Vaux fails to start with another ECU - Schnitzel
I have some performance chips to solder into the BOSCH ECU of my 1998 2.5TD Vauxhall Omega. I bought an identical replacement ECU off ebay, but when I fit that, the car refuses to start, if I put mine back it fires at the turn of the key.

I am wondering if this is some sort of security/immobiliser thing where chips in the key gets authorisation from the ECU to start?

My car came with a security code on a card in case the dealer needs to replace keys etc...but the seller of the new ECU doesn't have these.

Is this the problem (NON-MATCHING CODE) or am I barking up the wrong tree? Thanks
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Fri 11 Feb 2005 18:34
Vaux fails to start with another ECU - Dynamic Dave
I am wondering if this is some sort of security/immobiliser thing
where chips in the key gets authorisation from the ECU to
start?


Yep. You got it in one. If you fit another ecu, then you also need the appropriate chips for the keys.

If you can find someone who has a Tech2 diagnostic reader, they *should* be able to marry your existing key chips(s) up to the replacement ecu.
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Fri 11 Feb 2005 20:58
Vaux fails to start with another ECU - Schnitzel
Thanks Dave, I bet this turns into a saga!
The chips in the keys seem to be on the same PCB as the remote locking so if I swapped the key fobs, I think I would then not be able to use the alarm/locking. So I better have a word with TECH2 man and the locksmith (who can reprogamme new keys, but said he needs the security code)
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Sun 13 Feb 2005 16:28
Vaux fails to start with another ECU - John S
Nope, the problem isn't the keys. They have a fixed code which as Dave says has to be probgrammed into the ECU. To do this you need the security code which is specific to the ECU.

JS
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Wed 16 Feb 2005 08:13
Vaux fails to start with another ECU - Andrew Moorey (Tune-Up)
There is a way round it. If you are trying to fit a secondhand ecu you will also need the immobiliser which fits round the ignition barrel and the ignition key from the same donor car. The chip for the immob is inside the plastic bit of the key and the immob and ecu will still talk to each other.
Andrew
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Simplicate and add lightness!!
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