Hello, while driving, our 2011 XC90 turns off and displays a “immobilizer, see owners manual” message. My wife then pulls the key, reinserted and it fires up. This is intermittent. Like twice a month. After the first time, I changed the OEM Fob battery. It then happened again a week later. The only info on immobilizer messages I can find seem to be start up, not while driving.

-no issues starting up.
-new car battery 45 days ago. (Checking terminal tightness)
-new key fob battery
-Only one car key (do I need a second one?)
-no recent maintenance besides struts/shocks/brakes
-no aftermarket electronics or parts.

I just left the country for nine months, so I have to rely on her to trouble shoot.