My 2001 v70 has an electrical problem. The interior lights flash while driving and when I exit the v70 and lock it the alarm goes off. The dash board trouble indicator says the problem is the driver side rear door. The dealership replaced the door locks and they do not know how to fix the problem.

SOURCE: Alarm haywire, can't override anti-theft system or turn on car

The Alarm on my Mercedes ML320 sounded every night, then it started doing it more often, Showed it to the dealer he says it's the 'Tow Sensor', that needs to be repaced. $700, down the drain. I have already started hating this car, it eats $500-600, every 6 months...

SOURCE: 2001 volvo V70 T5 Problems

Had this same problem with a 2001 v70. Dealer needed to download new software to the computer. Took about 20 minutes and solved the problem. (The problem happened at 10 degrees below zero and I went in to see if they could tell me where the fuses for those circuits were located.)

Unfortunately the sofware re-load was not cheap.

SOURCE: Volvo S70 Alarm has become disabled

I HAD THIS PROBLEM ON MINE,TRY CLOSING THE BONNET FIRMLY (SLAM IT SHUT) TO SET THE BONNET SENSOR SWITCH PROPERLY.

SOURCE: 2001 Volvo V70-T5 fuel guage malfunction

I had the same problem plus the trunk light was off too. Pull out and wiggled all relays on rear fuse panel. It did not work. Then decided to do the dumbest thing to pull out all the fuses. Pull out #1, not bad. push it back in. The trunk lights lighted. Then check everything. All good.

SOURCE: 2001 v70 t5 wagon. auto all of a sudden dies while

First thing would do is check just how securely the battery leads are attached to the battery. Next have a look at the earth strap from engine to car frame connections. A complete cut out as you describe can only occur if there is sudden complete shut down of the electrical system, this would also account for the ECU not recording trouble codes, it needs at least to be on before it can record anything. The next check point would be the main fuse and starter relay and then the starter switch itself; there has to be break/loose connection somewhere in the 'on' circuit. This is not a 'short' otherwise the main fuse would have blown.