D.D. Palmer wrote:
> A good friend of mine has a year 2000 VOLVO S70 AWD with a mere 35,000 miles
> on it. I am posting this here because the VOLVO board is not very active and
> the problem is probably something you folks know about.
> My friends live here (Pittsburgh) but spent 6 months in Florida, hence the
> low miles. While they are in Fla each year the Volvo sits in their garage
> here. My job is to start it and drive it occasionally. In 2003, the battery
> died in spite of me driving it. I put in a DIEHARD for them. Again two weeks
> ago, I went to start the car to prepare for their return and, in spite of
> starting and driving all winter thru some bitter cold spells, the battery
> was dead and would not recharge after a jump and drive.
> Is there something in that car that drains the battery when it sits for,
> say, 2 weeks without being driven? And is there any reason NOT to disconnect
> the positive terminal next winter and perhaps move the battery into the
> warmer house? I also hear there is a "switch" that accomplishes the same
> thing as disconnecting the terminal. What about a trickle charger? Any
> danger of leaving one of those on with no one home and maybe for 2 weeks
> without inspection? Any ideas/thoughts on this relatively minor but annoying
> problem would be appreciated.
1. Yes, disconnect the battery to disconnect the parasitic (phantom)
loads. Just pop off one of the cables. Actually it is safer to muck
with the negative cable, but electrically they are equivalent.
2. If you leave it connected, it shouldn't discharge to flat-out dead
in two weeks. Either it isn't being charged, or there is an extra load
that you are not aware of. Is the glove box light on? Trunk light?
Under-hood light? Disconnecting a cable would, of course, take care of
any of these.
3. No, do not take the battery into a warmer place. A cold battery's
self-discharge rate is very small, but it increases at warmer
temperature. If you remove the battery from the vehicle, just set it on
the floor in the cold garage. The old wive's tale about not setting a
battery on concrete is just that - an old wive's tale.
4. I have never heard of an OEM disconnect switch. You can add an
aftermarket switch (a great big affair, since the current it must handle
is large), but why?
5. Take a look at http://www.batteryfaq.org/carfaq13.htm
for a lot of
information relating to your questions.
FWIW, I have a '98 Ford Ranger that still has the OEM battery. Every
winter, I leave the Ranger in my unheated garage in Maine for 6 months,
while I escape the cold. Before I go, I clean the battery terminals,
make sure the battery is fully charged (I drive the Ranger daily so this
happens automatically), and disconnect the negative battery cable. When
I get back to Maine in the spring, I simply reconnect the cable. The
Ranger has never failed to start right up, with no recharging, jumping,
or assists of any kind.