Brake Abs Warning Light problems of the 2004 Volvo S60

2004 Volvo S60 2. 5 turbo: no warning to the events. On numerous occasions, the car feels as if it has hit a large object, temporarily lurches and appears to momentarily stall creating a temporary loss of vehicle control. This is followed by an immediate loss of all instrument gauges, air conditioner, window controls and door locks. The fan did continue to work. The abs warning light also indicated as well as a warning that no brakes function existed. The srs service air bag urgent indication is illuminated. On turning the car off and restarting, the functions of the car return with exception that the srs service air bag urgent indication remains. This problem can take months to repeat or only a matter of minutes. It seems to be more prevalent in hot weather. The vehicle was taken to the service shop at the Volvo dealer and they could only clear alarms as they said the event created too many alarms/fault codes to troubleshoot. They downloaded new software revisions to each control module in the car. After a period of approximately a month, the events began occurring again. The vehicle has been taken to non oem mechanics as well and they are not able to troubleshoot the fault. The vehicle is scheduled to be taken to the dealers service shop again. Searching the internet chat rooms and blogs, as well as this site, there appears to be numerous other vehicles with this same safety fault that stalls vehicles in traffic and creates very sudden and severe lurches in power ultimately leading to a momentary stall out with loss of all instrument indications to include speed, rpm, turn indicator, etc.