Chanked my battery in my remote key fob for my Vauhall Astra and found that if you take more than 3 minutes (which I did)you need to reprogram it. Can you do this through the ignition or is it a main dealer job?
Some astras you had to insert the key in the ignition and turn it to the aux position while holding one of the fob buttons, I think the later astras you just need to use the key in the drivers door lock.
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