Ok, this is kind of a weird question, but there’s a reason for it. Hopefully you people who know something about cars can help me out.
How quickly (ballpark - days? 12 hours?) would you expect a car battery to completely drain (no electrical power at all - even the automatic locks won’t work) if the headlights are NOT left on, and there is nothing left plugged in, but an overhead light or something may have been left on?
If you found a car in this condition at 8 am, would it be feasible that it was driving around the night before?
What if I add the info that the mechanic got it started and got the battery charged, but didn’t do anything else to it, after which it was driven around and left it overnight twice with no problems.
[quote=“zyzzx”]Ok, this is kind of a weird question, but there’s a reason for it. Hopefully you people who know something about cars can help me out.
How quickly (ballpark - days? 12 hours?) would you expect a car battery to completely drain (no electrical power at all - even the automatic locks won’t work) if the headlights are NOT left on, [/quote]
From my experience, aprox 2 - 3 weeks. But it depends on the car/state of battery as well.
[quote=“zyzzx”]and there is nothing left plugged in, but an overhead light or something may have been left on?
If you found a car in this condition at 8 am, would it be feasible that it was driving around the night before?
[/quote]
Not sure i understand exactly what you mean, but if you mean left overnight with the inside light / reading light on, very feasible that the battery would drain itself out.
Quite normal, the alternator in the car will recharge the battery as you drive, so if the mechanic got it stated and you drive it around for a while, the battery should return to more or less a good state.
[quote]Ok, this is kind of a weird question, but there’s a reason for it. Hopefully you people who know something about cars can help me out.
How quickly (ballpark - days? 12 hours?) would you expect a car battery to completely drain (no electrical power at all - even the automatic locks won’t work) if the headlights are NOT left on, and there is nothing left plugged in, but an overhead light or something may have been left on?[/quote]
Weeks. Modern cars have a lot of electronics that stay active when the ignition is off, but they shouldn’t take a whole lot of juice. Lead-acid self-discharge rate is pretty slow.
Not necessarily. The fuel gauge would be a better indication! Unless you’ve got something wrong with your alternator, there’s no reason why your battery should ever be less than fully charged (~14V, unloaded). If you left something very small switched on (I mean, presumably you know exactly what was switched on?) then it could be your battery is a bit old and knackered. A 100-150Ah battery should last a couple of days even with the parking lights on.
The mechanic should have checked that there was a charge current with the engine running. Get a cheap meter and measure the discharge current (that is, current flowing out of the battery with everything switched off). If it’s not nearly-zero, you might have a partial short somewhere (maybe even inside the battery itself, if it’s old).
Thanks for the replies.
I actually have no idea what the mechanic did, that was just speculation.
Basically, someone is claiming that this car was in an accident. I know that it wasn’t, and that it wasn’t driven for at least 3 days before it wouldn’t start (dunno about before that). I’m wondering if the fact that it was so completely dead the morning after the supposed accident would provide some evidence that there’s no way that this car could have been involved.
Surely the fact that your car is completely undamaged and unmarked might provide some evidence? Although … logic isn’t one of the Taiwan justice system’s strong points.
As madracer says, if it was driven the night before then the battery couldn’t be flat (assuming you have a functioning alternator) because it would have charged during the drive. So yeah, it adds weight to your argument, but it’s not evidence. After all, any idiot can drain a battery to “prove” the car has been standing idle.
[quote=“finley”]Surely the fact that your car is completely undamaged and unmarked might provide some evidence? Although … logic isn’t one of the Taiwan justice system’s strong points.
As madracer says, if it was driven the night before then the battery couldn’t be flat (assuming you have a functioning alternator) because it would have charged during the drive. So yeah, it adds weight to your argument, but it’s not evidence. After all, any idiot can drain a battery to “prove” the car has been standing idle.[/quote]
I actually don’t know any of the details of the accident claim, cause it’s not my car - it’s a work car that gets loaned out for trips. But I was in possession of the keys at the time it supposedly happened, so I just got a call from an assistant asking me about it. Unfortunately the car gets driven a lot, and on some rough roads, so it’s plenty scratched up already. If they’re claiming it hit a bicycle or a person, the damage argument might not help…
Hopefully the ones actually in charge of the car will get this figured out, and I won’t get dragged into anything. But my second thought on hearing about this (after the ‘that’s impossible because I had the keys’ thought) was ‘that’s impossible because then the battery wouldn’t be dead’.
But I know jack-all about cars, so I wanted to get some idea of whether that actually has any merit.
Sound’s like you’re going to have to be very careful about this.
I would strongly advise collecting evidence that you were not the driver of the car. If the worst comes to the worst, having constructive possession of the car through possession of the keys is probably going to be enough for a prosecutor to launch a case against you with no other evidence at all - and if you can’t supply counter evidence (and even if you can), it could still be difficult to prove that you weren’t the driver of the car, or were not responsible in permitting another to drive the car.
Although the Taiwan courts follow a system of innocent until proven guilty, this, in my personal experience, is not the case. You are an easy target, so please be careful.
In all likeliness, nothing will happen and I don’t want to cause you unnecessary worry, but I’ve been caught out on more than one occasion for silly things like this and believe me, it is a real pain.
SH
there could well be another set of keys around that someone else has cut to “borrow” the car without telling.
Phew, as I suspected, someone was wrong and the car was not in accident on the night in question. It was the next night, after it was fixed, and when I was not in possession of the keys. So, not my problem, and the battery question is now moot.
Good. Glad to hear it.
[quote=“zyzzx”]Ok, this is kind of a weird question, but there’s a reason for it. Hopefully you people who know something about cars can help me out.
How quickly (ballpark - days? 12 hours?) would you expect a car battery to completely drain (no electrical power at all - even the automatic locks won’t work) if the headlights are NOT left on, and there is nothing left plugged in, but an overhead light or something may have been left on?
If you found a car in this condition at 8 am, would it be feasible that it was driving around the night before?
What if I add the info that the mechanic got it started and got the battery charged, but didn’t do anything else to it, after which it was driven around and left it overnight twice with no problems.[/quote]
It is impossible to evaluate the condition of your vehicle’s battery without getting my hands on it. I will say though that there are many sizes of starter batteries and all of which will have different amp-hour ratings. Also many cars have different levels or normal parasitic drain, which must also be taken into account in order to asses the state of your battery’s performance. Some of the heavier parasitic drain levels I have found tend to be on European Fords, which can be extremely high and would normally be considered a fault on most Japanese vehicles. It is therefore impossible to say with any degree of accuracy whether your battery is an issue or not.
You should perhaps consider testing for a parasitic draw on your battery however, before replacing it.
Tip: Some vehicles allow for a larger than standard battery to be fitted when replacing. Larger batteries of course can offer greater capacity as well as greater longevity. Personally I prefer traditional lead acid batteries which can be topped up with distilled water through removable caps on their tops. Commonly however more vehicles these days are fitted with “sealed” batteries which can’t be simply topped up and therefore often don’t perform as well as they dry up over time.
I’ve had that thought too, but distilled water does not seem to be an easy thing to buy in Taiwan. I know it can be ordered through chemical supply houses, but it’s not like in most Western countries where you can buy it at the supermarket. Well, at least not in Taitung where I am - I tried and failed. I asked at our one chemical supply company, and they said they could order it from Kaohsiung, and it had to be a large size (20 liters, if I remember correctly). I decided not to bother (I only wanted it for a steam iron).
I’ve had that thought too, but distilled water does not seem to be an easy thing to buy in Taiwan. I know it can be ordered through chemical supply houses, but it’s not like in most Western countries where you can buy it at the supermarket. Well, at least not in Taidong where I am - I tried and failed. I asked at our one chemical supply company, and they said they could order it from Kaohsiung, and it had to be a large size (20 liters, if I remember correctly). I decided not to bother (I only wanted it for a steam iron).[/quote]
I imagine drug stores would have it for general use, wouldn’t they? What’s in typical eyewash solution these days?
I’ve had that thought too, but distilled water does not seem to be an easy thing to buy in Taiwan. I know it can be ordered through chemical supply houses, but it’s not like in most Western countries where you can buy it at the supermarket. Well, at least not in Taidong where I am - I tried and failed. I asked at our one chemical supply company, and they said they could order it from Kaohsiung, and it had to be a large size (20 liters, if I remember correctly). I decided not to bother (I only wanted it for a steam iron).[/quote]
I imagine drug stores would have it for general use, wouldn’t they? What’s in typical eyewash solution these days?[/quote]
Sterile saline, I think.
You can get distilled water in bottles in the all-night hardware store places (There’s a Chinese word for them that’s been mentioned on here, but I can’t remember what it is). They don’t, however, label it as such in English, but as “battery conditioner” or some such.
Alternatively you could de-frost your fridge, or, more conveniently, collect the condensate from an air conditioner, which is available free in large volumes. The latter is essentially distilled water, but might have some traces of metals from the cooling coil (copper, lead from solder, for example) and airborne dust. Probably cleanest after rain.
Hmmm…how about rain water itself? I hadn’t really thought about that before, but I guess it would be the same as distilled, wouldn’t it? I live in a rural area, so air pollution isn’t an issue. Come to think of it, a little bit of acid rain might be even better for a battery.
In my experience, car batteries drain faster in Taiwan than in the US. I remember leaving my cars in the US in the garage for 2 months with no battery drain (clearly it’s not wise to leave a car untouched for so long, but occasionally you gotta). Here, cars sitting out for more than 2 weeks seem to lose enough battery power so that the car won’t start.
I’m basing this experience on 4 different cars in the US and 3 here.
Perhaps there’s something draining the battery like a car alarm.
[quote=“Chris”]In my experience, car batteries drain faster in Taiwan than in the US. I remember leaving my cars in the US in the garage for 2 months with no battery drain (clearly it’s not wise to leave a car untouched for so long, but occasionally you gotta). Here, cars sitting out for more than 2 weeks seem to lose enough battery power so that the car won’t start.
I’m basing this experience on 4 different cars in the US and 3 here.
Perhaps there’s something draining the battery like a car alarm.[/quote]
Maybe the alarm system as you said. But modern cars have all kinds of electronic crap that does drain battery power (though slowly) even when the car isn’t in use. If your Taiwanese cars were newer models than the American ones, maybe that’s why.
I have two old cars (actually, a van and a truck) here in Taiwan, and do not have the problem you describe. I’ve left them sitting for months without issues. Both were purchased circa 1997, and have no electronic crap whatsoever (and no car alarm).
Taiwan’s relatively mild winters (compared to most of the USA) should actually be better for a battery’s life span, if I’m not mistaken. I have noticed that batteries in cars here tend to be smaller size than in the USA, and I think that reflects the weather - you need a bigger battery to crank the starter when the weather is subfreezing.
One possibility: many of the original equipment batteries in cars here are crap, but replacement batteries are generally OK if you buy a good brand. So if you buy a NEW car here, you may be soon replacing the battery, but with a used car I would expect that the battery was already replaced at least once (though perhaps with another crap-quality battery).
Since I’m now in ranting mode: my van is a Mitsubishi Freeca, the truck is a Toyota Zace. The Mitsubishi came with all sorts of crappy original electrical components that quickly failed - bulbs, switches, the radio, air-conditioner. Rubber things were also crap (especially tires - replaced at 10,000 KM). Both of those hydraulic cylinders that hold up the rear door failed. I made sure not to replace with original Mitsubishi “quality” parts.
[quote=“Chris”]In my experience, car batteries drain faster in Taiwan than in the US. I remember leaving my cars in the US in the garage for 2 months with no battery drain (clearly it’s not wise to leave a car untouched for so long, but occasionally you gotta). Here, cars sitting out for more than 2 weeks seem to lose enough battery power so that the car won’t start.
I’m basing this experience on 4 different cars in the US and 3 here.
Perhaps there’s something draining the battery like a car alarm.[/quote]
Its the heat. Heat is a factor in battery discharge and also in battery life span. The hotter the climate, the shorter the lifespan.
Why do you need larger batteries in colder climates? Because batteries use a chemical reaction to produce electricity, but chemical reactions are slowed down in colder temperatures. It is colder temperatures however which increase overall battery lifespan and reduce slow discharge. Slow discharge and lifespan shouldn’t be confused with fast discharge rates however.
Simply put, hotter climates are worse for lead acid batteries overall and are often the reason for short periodic issues.
[quote=“Dog’s_Breakfast”][quote=“Chris”]In my experience, car batteries drain faster in Taiwan than in the US. I remember leaving my cars in the US in the garage for 2 months with no battery drain (clearly it’s not wise to leave a car untouched for so long, but occasionally you gotta). Here, cars sitting out for more than 2 weeks seem to lose enough battery power so that the car won’t start.
I’m basing this experience on 4 different cars in the US and 3 here.
Perhaps there’s something draining the battery like a car alarm.[/quote]
Maybe the alarm system as you said. But modern cars have all kinds of electronic crap that does drain battery power (though slowly) even when the car isn’t in use. If your Taiwanese cars were newer models than the American ones, maybe that’s why.
I have two old cars (actually, a van and a truck) here in Taiwan, and do not have the problem you describe. I’ve left them sitting for months without issues. Both were purchased circa 1997, and have no electronic crap whatsoever (and no car alarm).
[/quote]
Ditto. Battery got it running after 2 months standing in the open, which took a bit of cranking, I’m guessing because the carb had dried out a bit. Very old car, no electronics, no alarm.
Of course its not electronics per se that’s the problem. (I intend fitting transistor-assisted ignition, for example, and don’t expect that to drain the battery). I think its mostly down to computerised stuff that stays on and needs power to maintain volatile memory.
Incidentally MAPLINS in the UK were selling quite neat little 12V 2W photovoltaic “briefcases” that would, I imagine, be enough to keep your system indefinately online. 10 quid special offer. (They had bigger ones too).I was tempted but didn’t think I really needed one. Maybe something similar is available in Taiwan?
Hmmm…how about rain water itself? I hadn’t really thought about that before, but I guess it would be the same as distilled, wouldn’t it? I live in a rural area, so air pollution isn’t an issue. Come to think of it, a little bit of acid rain might be even better for a battery.[/quote]
Probably be OK but I THINK the chances are aircon condensate will be cleaner. If I understand how they work (never looked inside one) the cooling coil is inside the room so relatively protected from atmospheric dust.
If the aircon is dirty, this, along with health and efficiency (- NOT that “naturist” magazine, though it too was regarded as dirty once upon a time ) would be one more reason to give it a clean.