Using a trickle charger - any rules on this?

A manual charger that size won't do much. However if that battery has been drawn down that many times it is on borrowed time. I would replace the battery, then fix the warning chime. Unless that car was made before about 84-85 it has a lights on warning chime. The other option is to install a battery buddy. They monitor the draw on the battery and cut the power before it gets to low to fail starting the vehicle.

A 1 amp charger can be left on for a couple days and in fact a very slow charge is the best way to revive a completely discharged battery. Contrary to what many people believe, completely discharging a lead acid battery doesn't do much harm. Mostly, the damage is done when recharging it. I think you are looking at something like 3 days to charge a fully discharged battery with 1 amp.

-jim

y_p_w wrote:

When I use a portable jump starter I typically leave it on for a minute or so before disconnecting it. It should definitely charge up the jump starter's battery a bit, and I understand that it might also reduce the initial charging current to the car's battery. I've been told by some people that a lower initial charging current is critical to reduce battery capacity loss.

My 2004 Subaru Impreza WRX doesn't have a headlamp warning chime, but it does have a headlamp auto-off feature. Same goes for some relatives' Toyota Camry.

I did some research and I think I know what the problem is. Apparently the driver's side door open switch can get stuck to the closed position. I've noticed that the dome light doesn't turn on when the driver's side door is open and it's switched to the center (door selected) position. Apparently the headlamp-on warning or key- in-ignition warning chimes don't activate until the driver's side door is sensed open.

As a follow-up, I got home and checked it for this little switch. The first thing I noticed was that all three other doors worked fine with the dome light. Next, the little switch felt loose. I first tried prying it back (bending it) when I then noticed that there was a little hatch that opened to reveal the screw. The little switch was actually not connected to the rubber/metal switch cover. I think it was supposed to be grounded to the body via the screw, but the ground clips on the switch were always loose (might have even been shaking around in there never depressed).

So now when the driver's side door is open and the headlights are on, it gives off a loud whine. Of course it doesn't do anything when the map lights are on. :-(

Not Honda, no sir. They leave that for the HIGH END models. His Civic? Doesn't have one.

Toyota, on the other hand, just turns the lights off when you turn the car off and open the door. Not on ALL models, but pretty damn far down the line.

And I had a Subaru 20 years ago that just turned the lights on and off with the ignition. Pure simplicity.

Anyway, the fix to the Civic is simply to add a chime, aftermarket.

Tell your wife or teenager that the next time they leave the car light on and the battery drains, they will need to pay for a tow truck to come out for a jump...

End of problem, no trickle charger needed...

I've heard other

IIRC, batteries were damaged in the old days right in the showroom because of trickle chargers in the range of 1 -1.5 amps.

They might be left on charge for months ( thus making the dry charge battery a step forward).

You have at least two or three options: (1) Make sure all the lights and systems are off ( which sounds like it does not work for you and your present situation) (2) Buy a unit which will sense your battery condition, and disconnect it from the car's electrical system if the battery is discharged to a low level. (Google for them. They exist) (3) Use the trickle charger as a matter of course. I dont like to leave a battery a long time with

1 amp or more of charge, so I sometimes put a 12 v lamp in series with the leads and decrease the charge rate to a (bias level) 100-250 ma. Dead simple, and works fine. Wattage of the lamp determines the resistance, so you can select values to limit your charge.

Turns out it did, and the advice that it should be fixed was sound. It's a really loud continuous whine too. There would be no mistaking that.

Well - the deal is that I'd end up paying for it, and occasionally I'm the guilty party from turning on the lights during the day (typically for visibility in forest roads).

The map lights however are usually not my fault and typically they only require a jump if left on overnight or for days at home.

I have a Sears battery minder/trickle charger/whatever it is called.It works ok.Sometimes I actually use it. cuhulin

If it's a manual charger then you have to watch it. If it's a sealed battery then you can't check the specific gravity so it's more difficult to determine when the battery is fully charged. Personally I like to use a Smart Charger and periodically use the Desulfate and Equalize features, especially if one or two cells are a bit lower than the others. If the Smart Charger shuts off and I don't think it's quite done yet (all cells not equal) then I'll use a 1/2-1 amp charger for an extended period of time, checking it regularly. But I don't think, under most circumstances, that you can properly recharge a car battery with that low of a charge rate if it's considerably discharged.

Don't be such an enabler. Tell the kid to get his ass off his computer and get a job--- and the old lady too.

And if your cognitive skills are such that you repeatedly leave your lights on while driving in the woods, how are you going to remember to hook up the charger every time you bring your car home? Also, a guy like you should think twice before venturing out in the woods so dark and deep. You'll get lost for sure and the fire department, cops or forest service will end up wasting hundreds of thousands of taxpayer dollars mounting a search for you...

Uh yeah.

Really - I got used to the headlamp switching off with the ignition on my Subaru. My wife has also forgotten. It's not going to be a problem now with the door-open switch fixed.

Didn't I mention that I always carry one of those portable battery jump starters? I remember once driving the Civic to Lassen Volcanic National Park, accidentally leaving the lights on for about an hour at the trailhead. When I got back the starter wouldn't turn, I went to the trunk to get the jump starter, and opened the hood to connect it. Then a law enforcement park ranger came up, noticed the car with the hood up, and asked if I needed a jump. I showed him the jump starter, briefly explained what it did, and he said it sounded like a good idea. This happened to be with the factory battery, which has since been replaced.

That jump starter has helped out a bunch of time with weak/dying batteries (before getting a replacement), lights on, etc. I've actually used it several times to help friends or complete strangers start their cars. It's a heck of a lot easier than trying to get batteries close enough to each other and/or jumper cables that are long enough. It's also great when I can't flag anyone down for a jump.

So far nobody's had to fish me out on the trail. In fact once I helped a lost kid (separated from his high school group) find his way back to the trailhead. Otherwise they might have sent out search teams to find him.

We had a nice little old aunt who could not remember to close the doors, or glove compartment, or anything else on her new Avalon. She would buy meat and leave it in the trunk for several days.

Finally, the family removed the map light, interior lights and trunk light. That stopped the dead batteries but not the roadkill smell.

~1amp is pretty much a "maintainer". It may charge a batter but will take a long time. A 2/4/6 or 2/4/10 electronically controlled charger would be a better choice. That should get you close to the standard C/

10 rate. They typically have 2-3 modes depending on how discharged a battery is. Then they go into trickle mode after that.

Not a key chime--a headlights on chime. THAT'S what he's missing. He leaves the headlights on, and that runs down the battery.

If you are concerned with 1 amp overcharging the battery then all one has to do is plug the charger into an automatic timer set for a few hours a day.

I've done this with NIMH batteries and low amperage dumb chargers. With this method you can't ruin the batteries and you'll always have a spare set of fully charged batteries.