I have travelled on the AVE between Málaga and Madrid many times. Luggage has to be put on a conveyor belt and go through an airport type scanner, but never have I had to empty mine before it is scanned! I suppose if something suspicious showed up in a bag, the security officer would have to ask for it to be opened and inspect the contents, just as they do at airports. Having seen how long the queues are of passengers waiting to board, it would take hours if everybody had to empty their bags and have them inspected before boarding!

It might be a good idea to remove the padlocks before putting your bags through the scanner, though, to avoid a delay being caused if you were asked to open them if the security officer wanted to have a closer look at something.

This is what the scanners look like

El control de seguridad para subir en el AVE (astelus.com)

Mine wasn't emptied. I guess there's more chance of being asked to open your bag if the machine finds something which looks similar to something they don't like, similar to airports.

And if you've just arrived on a flight, the chances of that happening would be minimal I guess?

Thanks! Thats helpful, and as I now know its going to happen I can sort out keys etc rather earlier than I normally do!

Hopefully! At least I'm now prepared for yet more queueing, and thus I know there's no way of making the earlier train!

Feedback as promised 😊

i had to get wheelchair assist through the airport at Madrid, recommended by Iberia at check in at LHR, glad I did, it would have been a long walk. No queues but a very long distance comparable with LHR.
very smooth and fast with no queue at passports or health, showed my Aussie vax cert at check in and Health in Madrid but wasnt asked for the SpTH QR thingy at all.

Taxi from outside to the RENFE at Chamartin, fast and easy. Plane landed 13.00, made the 14.30 train very easily.
Bags were put through an xray/conveyor belt by the grumpiest guy I have met in Spain all week

Lift was broken so I resorted to limping with bags to the escalator, all staff left in a hurry (so fast it was funny ) so several lovely people helped me down the escaltor.
Train to Santiago was amazing. Stunning scenery, clean, spacious,fast, and with a great trolley service.

much easier than expected & thanks to everyone who helped with info 😎

Thanks for feedback, glad you had a successful outcome to the journey.

Twas great, happy to answer any odd queries from future travellers
I would definitely recommend the RENFE fast train Madrid to S de C, amazing scenery!

It's always good to have someone later mention how things went. Thanks.