Electrical problem, poor running/not running

[Faust]

'04 V70 N/A To begin at my beginning. Yesterday as I sat in front of a coffee shop with engine running and radio playing, the radio quit. Wouldn't restart so I shut off engine. Engine wouldn't restart. Got a jump locally and started immediately, Ran at 1200 rpm, wouldn't respond to throttle, quit wouldn't restart. Had it towed home. Checked the usual and put charger on battery. If I switch charger to "start" it starts. Runs erratically, slight response to throttle, rpm drops them quits. I notice fuel gauge quits when engine does. Engine will not restart, some solenoid click (or similar). Wait five minutes, engine starts, Runs smoothly, rpms drop and quits. Will not immediately restart, needs five minutes with charger attached. I am a poor electrician, but I seem to be getting 11 volts from battery, without charger attached. Any guesses, would poor battery do this? I should think it would run on the charger.

At other times, when it quits, I seem to get 6 volts at battery, There has been no gradual deterioration, it ran fine, until it just quit while idling.

[93SCMax]

Replace your battery. Double check combi belt condition and tension. If these don't fix it, then you see if the alternator is generating the proper voltage. Focus on the battery 1st. Don't forget to use the battery reset procedure or you'll have door lock and sunroof issues.