if you've tried a battery and the remote still doesn't work, assuming the battery is up the right way. Then you need a new remote. You have to buy a new key, can't buy the remote on its own. And you need the car there so the key can be coded to the car.
Thats why they (we) need the car, its a bit hard for our laptop to communicate with a black box sitting on a desk. Communication is via the
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