2004 V70 manual trans. This car has been very good to me for a long time, now I am having an issue that I don't know where to begin fixing? For a couple of days some random dash lights were flickering, and random messages were showing. Radio lights were not on, sunroof wasn't getting power,...I figured since the car had its original battery, and after 10 years in the NE elements and 230,000 miles it was time for a new one. I put in a new battery, and bang, it fired right up and the lights were gone like nothing ever happened. So I thought the problem was solved. I then drove about 2 miles to the gas station, turned the car off, gassed up, and then it would not restart. It was just clicking like it had a weak battery. I then walked home and got my jump pack, went back and hooked it up, and it started once again. I drove it home with the jump pack connected, and made it back, but the dash lights were flickering around. Once home I turned it off and tried to restart with no luck. I have to think the new battery could not have did that quickly even if it were a bad alternator? I tried to 'wiggle' the cables on the solenoid and they seem tight, I did clean the terminals and cables when reinstalling new battery. I was checking to see if there is a common issue with this model that anyone knows of that could be the culprit? I saw the red junction block with a bunch of wires coming out of it next to the battery. I guess that could be corroded, but seems unlikely. Thanks!

About one year ago my 2004 v70 had a number of what appeared to be electrical
issues occur (doors not locking, sun roof not working, etc.) This site
has information that when the alarm module battery goes bad it creates a number of what appear to be unrelated problems. When I checked the alarm battery it was shorted. replacing the moduoe corrected the problems I was having.

The module you speak of certainly could be the issue. I did look in to replacement and it looks time consuming and the part is fairly expensive. I don't mind doing it, but I don't want to start replacing parts until I have a high degree of certainty that it is that part. After the previous response from afm, and a bunch of reading I feel it could be the alternator or the module as the likely culprits. If the alternator has a short internally I understand it can cause the same issues I am having, and it is a no-name rebuilt alternator in the car. Does anyone know if the testers at advance auto parts store can test for shorts or just output with the alternator on the car? I would like to rule the alternator out before buying anything.

I read in one place that the alarm siren module has to reprogrammed when it is replaced. Is this true?

I concur... be sure it is the alarm module. I am not aware many cars have the alarm module battery problem. I bought mine from Tasca Volvo on
line. I did not have to reprogram it.

A new battery can be bad. Check the voltage at the battery with and without the engine running.

Greg