1998 Volvo S70 and dead battery

I have replaced the battery and had a new alternator put in, but every other day the battery is dead. I read that perhaps a Group 48 700 CCA battery would help?


A battery shouldn’t die by itself with the car just sitting there. You more likely have something draining the battery, like a dome or trunk light.

Nope - trunk light disabled. I had the battery recharged to full capacity 10 days ago. Every day when I start the car, you can tell the battery is getting lower…I turn everything off when parked.

Have you had the charging system checked? My cousin’s '99 S70 had a slightly loose nut on the charge line connection at the alternator, and had similar battery problems. Simply getting this hold-down bolt tightened fixed her problem. There also may be other reasons why the alternator is not charging the battery, like a blown fuse. A simple check is, with the engine running, put a volt meter across the battery terminals. The alternator should be putting out 13.5V to 14.5V to charge the battery. If it is less, the battery is not being charged.

You most likely have a parasitic current drain on the battery. Something is drawing excessive current from the battery while the car is parked. Have a shop check that out. Normal current draw should be around 15 to 20 milliamps.

Disconnect the negative cable after you are through with the car for the day. Reconnect it the next morning and see if the battery turns the engine over normally. If it does, you have something draining the battery.

Try the glove box light, as they tend to stay on

I’m going with Cougar and RemcoW with a parasitic drain. The fact that your trunk light is disabled and you turn everything off is irrelevant. Some draw on the battery always remains, and it can be too much for various reasons.

I wouldn’t suggest disconnecting the battery or a haphazard search process. There is no reason it should remain a mystery. If you have an electrical multimeter there are probably 101 websites that will give a systematic approach to checking for the drain and finding out what it it.

Of course, it would also take about a minute with a meter to make sure the battery is getting an adequate dose voltage from the alternator as BustedKnuckles mentioned. So I would rule that out first and then go on to checking for drain.