My remote does not allowed me to lock or unlock my car it already has a new battery in the transmitter
The owners manual is no help. For one thing, the "official" site wants your credit card, then http://justgivemethedamnmanual.com/honda/honda-accord-owners-manuals does not have coupe. And yes, it matters. Then another one re-directed to Porn. (*Sigh*) so no more excuses, but I was trying to find fuse for BCM, (Body Control Module), and no success there. But if you remove the cover to fuse box, hopefully there is a map of fuses. Look for BCM. That is MAYBE the culprit. As long as I understand that when you say 'transmitter' you mean fob.
Did you brighten up the contacts with a scotch bright pad before putting in new battery? Lots of auto parts store can test remote for signal.
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