battery drain

Hey folks,


I have an 89 Jetta GL 5speed. Original motor and trans. Thursday I drove the
car all over Memphis and got home a couple hours after my little road tour
and parked the car.

Lights were off, radio disconnected (detachable face) and went in the house.
I came out a few hours later and the battery was pretty much dead.


I put the battery on a 10amp charge and it charged back up within an hour.

I put it in the engine compartment but did NOT connect it since i wanted to
see if there was a drain from the system or if the battery was starting to
give out.

*note: battery is only 1 year old

So yesterday (24hrs after charging) I hooked the battery back up, turned the
ignition and if fired right up. Drove it around for about 5 minutes and
parked it.

I checked it two more times during the day, both times about 1 hour apart.

On the second try, battery was dead.

So, before I take it to Metric and have them trace the problem, is there
anything I can do to try and _find_ the problem myself ? I've never traced
an electrical problem before so any pointers would be helpful.

*other things of note: there was some corrosion on the positive battery
connector.

Finally, could it really _be_ the battery ?


TIA

Chris

In rec.autos.makers.vw.watercooled, Chris Etzel
> wrote:

>
>
>I have an 89 Jetta GL 5speed. Original motor and trans. Thursday I drove the
>car all over Memphis and got home a couple hours after my little road tour
>and parked the car.
>
>Lights were off, radio disconnected (detachable face) and went in the house.
>I came out a few hours later and the battery was pretty much dead.
>
>
>I put the battery on a 10amp charge and it charged back up within an hour.

Charging 1 hour at 10 amps could, at most, charge the battery to 10
amp-hours. Plus, a "10 amp charger" might only be charging perhaps 5
amps after a bit. So you may have only had a partial charge into a
10 amp-hr battery.

>
>I put it in the engine compartment but did NOT connect it since i wanted to
>see if there was a drain from the system or if the battery was starting to
>give out.
>
>*note: battery is only 1 year old
>
>So yesterday (24hrs after charging) I hooked the battery back up, turned the
>ignition and if fired right up. Drove it around for about 5 minutes and
>parked it.
>
>I checked it two more times during the day, both times about 1 hour apart.
>
>On the second try, battery was dead.
>
>So, before I take it to Metric and have them trace the problem, is there
>anything I can do to try and _find_ the problem myself ? I've never traced
>an electrical problem before so any pointers would be helpful.

An ammeter in series with the battery with all car loads off would
be the normal way to troubleshoot. Normal draw would be maybe 10
ma??? (1/100 amp)? Well under an amp anyway. So if you had more, you
would look for loads that are not letting go-- such as the relay
that drives the rear window defroster grid.

Another way that can serve without a meter is to connect and
disconnect the negative terminal battery with loads off. You can see
better out of the sun. Do you see a spark? If so, look to loads
being engaged. Pull fuses etc to try to find the cause, or engage
somebody to track this down for you. A good mechanic would be
efficient. Your friends might get into it if you have more time.
Troubleshooting that stuff can be fun if you are not time-sensitive.

>
>*other things of note: there was some corrosion on the positive battery
>connector.
>
>Finally, could it really _be_ the battery ?
>

Yes, but it seems less likely based upon what I am reading.

One safety comment: remove the negative terminal first and attach it
last. That way if your wrench touches the chassis, there is no
fire/explosion.

And while you are troubleshooting, you can just keep that one
terminal disconnected rather than moving the whole battery to the
back seat.

In rec.autos.makers.vw.watercooled, Chris Etzel
> wrote:

>
>
>I have an 89 Jetta GL 5speed. Original motor and trans. Thursday I drove the
>car all over Memphis and got home a couple hours after my little road tour
>and parked the car.
>
>Lights were off, radio disconnected (detachable face) and went in the house.
>I came out a few hours later and the battery was pretty much dead.
>
>
>I put the battery on a 10amp charge and it charged back up within an hour.

Charging 1 hour at 10 amps could, at most, charge the battery to 10
amp-hours. Plus, a "10 amp charger" might only be charging perhaps 5
amps after a bit. So you may have only had a partial charge into a
10 amp-hr battery.

>
>I put it in the engine compartment but did NOT connect it since i wanted to
>see if there was a drain from the system or if the battery was starting to
>give out.
>
>*note: battery is only 1 year old
>
>So yesterday (24hrs after charging) I hooked the battery back up, turned the
>ignition and if fired right up. Drove it around for about 5 minutes and
>parked it.
>
>I checked it two more times during the day, both times about 1 hour apart.
>
>On the second try, battery was dead.
>
>So, before I take it to Metric and have them trace the problem, is there
>anything I can do to try and _find_ the problem myself ? I've never traced
>an electrical problem before so any pointers would be helpful.

An ammeter in series with the battery with all car loads off would
be the normal way to troubleshoot. Normal draw would be maybe 10
ma??? (1/100 amp)? Well under an amp anyway. So if you had more, you
would look for loads that are not letting go-- such as the relay
that drives the rear window defroster grid.

Another way that can serve without a meter is to connect and
disconnect the negative terminal battery with loads off. You can see
better out of the sun. Do you see a spark? If so, look to loads
being engaged. Pull fuses etc to try to find the cause, or engage
somebody to track this down for you. A good mechanic would be
efficient. Your friends might get into it if you have more time.
Troubleshooting that stuff can be fun if you are not time-sensitive.

>
>*other things of note: there was some corrosion on the positive battery
>connector.
>
>Finally, could it really _be_ the battery ?
>

Yes, but it seems less likely based upon what I am reading.

One safety comment: remove the negative terminal first and attach it
last. That way if your wrench touches the chassis, there is no
fire/explosion.

And while you are troubleshooting, you can just keep that one
terminal disconnected rather than moving the whole battery to the
back seat.

In rec.autos.makers.vw.watercooled, Tom's VR6 wrote:

>
>Charging 1 hour at 10 amps could, at most, charge the battery to 10
>amp-hours. Plus, a "10 amp charger" might only be charging perhaps 5
>amps after a bit. So you may have only had a partial charge into a
>10 amp-hr battery.

I meant into a 50 amp-hr battery.

In rec.autos.makers.vw.watercooled, Tom's VR6 wrote:

>
>Charging 1 hour at 10 amps could, at most, charge the battery to 10
>amp-hours. Plus, a "10 amp charger" might only be charging perhaps 5
>amps after a bit. So you may have only had a partial charge into a
>10 amp-hr battery.

I meant into a 50 amp-hr battery.

Chris Etzel > wrote in message >...
> Lights were off, radio disconnected (detachable face) and went in the house.
> I came out a few hours later and the battery was pretty much dead.
>
> I put the battery on a 10amp charge and it charged back up within an hour.
>
> I put it in the engine compartment but did NOT connect it since i wanted to
> see if there was a drain from the system or if the battery was starting to
> give out.
>
> *note: battery is only 1 year old
>
> So yesterday (24hrs after charging) I hooked the battery back up, turned the
> ignition and if fired right up. Drove it around for about 5 minutes and
> parked it.
>
> I checked it two more times during the day, both times about 1 hour apart.
>
> On the second try, battery was dead.
>
> So, before I take it to Metric and have them trace the problem, is there
> anything I can do to try and _find_ the problem myself ? I've never traced
> an electrical problem before so any pointers would be helpful.
>
> *other things of note: there was some corrosion on the positive battery
> connector.
>
> Finally, could it really _be_ the battery ?

One option is to measure the draw (WITH THE CAR OFF)--use an ammeter
inline between the battery positive and battery cable (i.e. disconnect battery
positive cable from battery, use ammeter or multimeter between battery
and cable, and see draw); if you notice a significant draw, start pulling fuses
one at a time until it goes away. The fuse you just pulled is for the problem
circuit, which most likely is either (a) stuck on, a la a trunk light with a bad
switch or (b) has a short to ground of some sort that allows for ongoing drain
even when it should be off. Note that most cheaper multimeters have
low-current ammeters; mine tops out at 10A (unfused, no less, but that's why
I got the warranty), so you should be fine doing this for a small drain but
would probably be ill-advised to do it for a particularly large one.

Another option, somewhat less scientific, is to pull a few fuses each time you
park the car and narrow it down that way. Of course, you might want to make
sure you have a source for a jump if you don't happen to pull the right fuses,
but you should eventually figure it out.

Finally, don't forget to check general charging system health; I went through
three alternators on my Jetta before realizing that the alternator cable had
corroded inside one of the end lug connectors, so it would make a good
connection wiggled one way and not the other (and eventually fell out
altogether with the connector still on the starter bolt, hence me noticing).
So you should probably check the condition of the battery cables as well
as the starter->alternator cable (corrosion on the ends should be at least
cleaned up and may indicate more serious corrosion inside the cables that
needs to be addressed) and the output of the alternator. I'd expect that,
given the scenarios you've described, the alternator is probably working at
least reasonably well; however, poor general charging system health will
exacerbate a slow drain pretty quickly.

Chris Etzel > wrote in message >...
> Lights were off, radio disconnected (detachable face) and went in the house.
> I came out a few hours later and the battery was pretty much dead.
>
> I put the battery on a 10amp charge and it charged back up within an hour.
>
> I put it in the engine compartment but did NOT connect it since i wanted to
> see if there was a drain from the system or if the battery was starting to
> give out.
>
> *note: battery is only 1 year old
>
> So yesterday (24hrs after charging) I hooked the battery back up, turned the
> ignition and if fired right up. Drove it around for about 5 minutes and
> parked it.
>
> I checked it two more times during the day, both times about 1 hour apart.
>
> On the second try, battery was dead.
>
> So, before I take it to Metric and have them trace the problem, is there
> anything I can do to try and _find_ the problem myself ? I've never traced
> an electrical problem before so any pointers would be helpful.
>
> *other things of note: there was some corrosion on the positive battery
> connector.
>
> Finally, could it really _be_ the battery ?

One option is to measure the draw (WITH THE CAR OFF)--use an ammeter
inline between the battery positive and battery cable (i.e. disconnect battery
positive cable from battery, use ammeter or multimeter between battery
and cable, and see draw); if you notice a significant draw, start pulling fuses
one at a time until it goes away. The fuse you just pulled is for the problem
circuit, which most likely is either (a) stuck on, a la a trunk light with a bad
switch or (b) has a short to ground of some sort that allows for ongoing drain
even when it should be off. Note that most cheaper multimeters have
low-current ammeters; mine tops out at 10A (unfused, no less, but that's why
I got the warranty), so you should be fine doing this for a small drain but
would probably be ill-advised to do it for a particularly large one.

Another option, somewhat less scientific, is to pull a few fuses each time you
park the car and narrow it down that way. Of course, you might want to make
sure you have a source for a jump if you don't happen to pull the right fuses,
but you should eventually figure it out.

Finally, don't forget to check general charging system health; I went through
three alternators on my Jetta before realizing that the alternator cable had
corroded inside one of the end lug connectors, so it would make a good
connection wiggled one way and not the other (and eventually fell out
altogether with the connector still on the starter bolt, hence me noticing).
So you should probably check the condition of the battery cables as well
as the starter->alternator cable (corrosion on the ends should be at least
cleaned up and may indicate more serious corrosion inside the cables that
needs to be addressed) and the output of the alternator. I'd expect that,
given the scenarios you've described, the alternator is probably working at
least reasonably well; however, poor general charging system health will
exacerbate a slow drain pretty quickly.

"Chris Etzel" > wrote in message
. ..
> Hey folks,
>
>
> I have an 89 Jetta GL 5speed. Original motor and trans. Thursday I drove
the
> car all over Memphis and got home a couple hours after my little road tour
> and parked the car.
>
> Lights were off, radio disconnected (detachable face) and went in the
house.
> I came out a few hours later and the battery was pretty much dead.
>
>
> I put the battery on a 10amp charge and it charged back up within an hour.
>

Then it isn't holding too much charge. It should take several hours to
recharge. Take it in & get it checked - how old is this battery anyway?

I.

"Chris Etzel" > wrote in message
. ..
> Hey folks,
>
>
> I have an 89 Jetta GL 5speed. Original motor and trans. Thursday I drove
the
> car all over Memphis and got home a couple hours after my little road tour
> and parked the car.
>
> Lights were off, radio disconnected (detachable face) and went in the
house.
> I came out a few hours later and the battery was pretty much dead.
>
>
> I put the battery on a 10amp charge and it charged back up within an hour.
>

Then it isn't holding too much charge. It should take several hours to
recharge. Take it in & get it checked - how old is this battery anyway?

I.

et wrote:

> Hey folks,
Thanks for all the help folks.

I recharged the battery again overnight on a 2amp trickle with much better
results. Its reading 13.5 volts now. I noticed a lot of corrosion on the
positive connector and post (we've had like 200 tons of rain in the past 2
weeks) so I cleaned the post, replaced the connector and its running fine.


Chris

>
>
> I have an 89 Jetta GL 5speed. Original motor and trans. Thursday I drove
> the car all over Memphis and got home a couple hours after my little road
> tour and parked the car.
>
> Lights were off, radio disconnected (detachable face) and went in the
> house. I came out a few hours later and the battery was pretty much dead.
>
>
> I put the battery on a 10amp charge and it charged back up within an hour.
>
> I put it in the engine compartment but did NOT connect it since i wanted
> to see if there was a drain from the system or if the battery was starting
> to give out.
>
> *note: battery is only 1 year old
>
> So yesterday (24hrs after charging) I hooked the battery back up, turned
> the ignition and if fired right up. Drove it around for about 5 minutes
> and parked it.
>
> I checked it two more times during the day, both times about 1 hour apart.
>
> On the second try, battery was dead.
>
> So, before I take it to Metric and have them trace the problem, is there
> anything I can do to try and _find_ the problem myself ? I've never traced
> an electrical problem before so any pointers would be helpful.
>
> *other things of note: there was some corrosion on the positive battery
> connector.
>
> Finally, could it really _be_ the battery ?
>
>
> TIA
>
> Chris