Keyless drive problem

[2cav8]

Plenty of threads on keyless entry, but really they all seem to refer to remote locking/unlocking.
My problem started with a flat battery in my 2007 S80 V8, and after charging, a loose fitting battery negative terminal. After charging the battery and repairing the loose terminal, the remote lock/unlock wouldn’t work. It’s highly likely that the loose terminal might have produces a few sparks/intermittent connection when reconnecting the battery.
Using a sequence with the driver door window switches restored the remote lock/unlock functions, but still no keyless entry keyless lock or keyless start.
The car starts ok with either remote in its slot by the start button, but otherwise gives key not present message.
Obviously the keyless system no longer recognised either key.
Anyone know how to resolve this.