Everything worked fine earlier today, go out to the car and keyless go - doors wont open and start button won’t work. Checked fuse and it was fine. Batteries in keys ok. Could low car battery cause this problem?Key fob itself unlocks doors fine and starts car...just keyless go doesn’t work.

Do you have spare key to check?

Have tried with both keys and have tried putting new batteries in both keys - no luck.

also checked the keylessgo fuse and it looked fine.

Reason i wondered about the car battery possibly being the culprit is that it’s the original battery from 2011 still and have noticed plug-in accessories (phone chargers, dash cam, etc) are Turing off randomly while in use over the last few days

Ok. I do not have keyless function. I can measure the battery voltage with key.
I do not know how in keyless.
I turn the key to position 1, just before ignition.
Then I press the buttons of the screen in order to show total kilometers.
At this point you press three times the R button, a beep is heard and the voltage of the battery is shown.

I pulled the fuse, checked it, and out it back in, now all is good and Keyless Go is working as it should.