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Matt, Mechanical Engineer
Category: Audi
Satisfied Customers: 237
Experience:  BEng hons Mech engineering, in auto industry 22 years
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Just replaced 4B0 927 156AC gearbox ecu with identical numbered

Customer Question

Just replaced 4B0 927 156AC gearbox ecu with identical numbered unit after original was water damaged beyond repair. Cannot get reverse - any ideas?
Submitted: 4 years ago.
Category: Audi
Expert:  Shantal-Mod replied 4 years ago.


I've been working hard to find a Professional to assist you with your question, but sometimes finding the right Professional can take a little longer than expected.

I wonder whether you're ok with continuing to wait for an answer. If you are, please let me know and I will continue my search. If not, feel free to let me know and I will cancel this question for you.

Thank you,


Customer: replied 4 years ago.

I'll give it until Friday 14:00 then cancel please.



Expert:  Shantal-Mod replied 4 years ago.

Hello Nigel,

Thank you for getting back to me. We will continue to look for a Professional to assist you.

Thank you for your patience,


Expert:  Billy replied 4 years ago.
Hello and welcome! I'm Billy and i will assist you with this.

My apologies for the delay, thank you for your patience.

Are you sure the ECU you bought is good?
can you check the fault codes, and the live data of the transmission (using a scan tool)?
Customer: replied 4 years ago.

Hi Billy, Apologies for delay but I didn't know I had a reply. I'm told the ecu was working prior to removal. The scan tool reported fault codes 18232,18227and 18171.