C3 gearbox ECU

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C3 gearbox ECU

Post by Cunwina »

Please help where can I find the gearbox ECU so I can find the serial number. Also if I get this repaired can I plug it straight back in and will everything still work as before
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Re: C3 gearbox ECU

Post by GiveMeABreak »

To answer that we need you VIN so we know what you have.

Although there is no programming involved if replacing for exactly the correct part, you will have to read the oil wear counter from the existing ECU using a suitable diagnostic tool and transfer this reading to the new ECU. If you don't your replacement ECU will have the readings from the donor vehicle (id second hand) and this will affect the operation of the gearbox as they adapt their operation to the length of time the oil has been in the gearbox.
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Re: C3 gearbox ECU

Post by Hell Razor5543 »

It is safe to post the VIN in the thread, as the forum software will automatically obscure it so that only Forum staff can read it.

Oh, :welc: to the Forum, by the way.
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Re: C3 gearbox ECU

Post by wheeler »

You don't say what year the C3 is or if its a sensodrive or not but the gearbox ECU is normally right on top of or at the front of the gearbox.
Whats wrong with it? gearbox ECU failures are quite rare unless its water ingress? The software is updateable on the gearbox ECU, has this been tried?
You can also use a 2nd hand one no problem.