My 2000 S80 T6, started about a week ago and died as soon as I put it in gear. I had it towed to a mechanic that tested fuel pressure spark... and found out that after disconnecting the battery, to reset the computer it started. They gave it back to me and the next couple of days it did the same thing. So I disconnected the battery cable, put it back on and it started... Since then I was on the highway and the service transmission at next service came on the message center, and then the brake failure light came on a few starts later, and then the dash gauges went to zero but I could still drive. I shut the car off and to my surprise it started with nothing but the tranny message. It has since done all of the above on different occasions. What do you think?

Thanks

Brian

 

Check the box next to the battery where the red cables goes it might be loose. i would check all those wiring at first.