2004 Volvo S60 - intermittent power/electrical issue

So going in reverse order my car has been intermittently losing power. Seems to occur when car is turning/decelerating to low speeds. Thoughts?

December 2010 (cold): Driving without issue, then no power steering on hard turn into driveway. No issue pulling into parking space. Later that day, car loses power (brakes,steering) and all lights alarm. Turn car off, then on. No issues, pull into parking spot. Have car towed. Serpentine belt is fine. No obvious problems. Mechanic has tried driving car, but can not recreate problem. So many wires, is it hardware or software? Where to begin ??

December 2009(very cold): Decelerating to turn into parking lot. Car loses all power (as above)and can’t make turn. Treat problem as isolated event, theorize that bad gas may have caused stall.

July 2009(very hot): Car suddenly loses power (as above) when turning out of parking lot. Volvo dealer diagnoses problem at “dirty throttle module” and cleans it.

2006-2009: No problems with car. Purchased certified pre-owned.

When you say “loses power” are you saying the motor has stalled? Which means you need to turn the key to restart the motor, correct? At this point the symptoms aren’t really clear about what is happening.

Has anyone cleaned the battery terminals at the battery, and also the other end where the electrical connections are on the motor? If not, worth a try.

When the event happens the power steering goes out, the anti-lock brakes fail, everything alarms. It feels like the car “dies” and it continues to drift in whatever direction it was previously traveling. I have always immediately put it into park and restarted the car at which point it has full power, no alarm lights, no messages in box that alerts you to service/maintenance needs. As it only happens out of the blue (when turning off of a busy street) I have been focused on not getting rear-end/struck by anyone else, but I would say that yes the motor stalls.

On first glance the mechanic said everything looked in order, then they have been driving the car to recreate the problem (no luck so far), and now they are looking at the wires and connections.

It seems like the process is like looking for a needle in a haystack so I was hoping others might have encountered this problem in the past.

Of note the car has low mileage (about 48,000) and has had no other service issues and no accidents.