The battery on my Volvo keeps dying. How should I determine and fix the problem?
I have a 1996 Volvo 850 GTL Wagon. We drive it infrequently, averaging 2 trips per week. If it isn't driven in 10 - 14 days, the battery will invariably be dead, and I'll need to jump start it, or charge it with a trickle charger overnight.
At first, I thought the battery was worn out even though it was wasn't quite to the end of its warranty period. I replaced it, but this didn't solve the problem.
Next, I thought our typically short trips weren't allowing the battery to fully charge, so I specifically changed my driving habits and used the trickle charger to top up the battery on a regular basis. After doing this, the battery would measure in the 12.3 to 12.6 V range, but after two weeks without driving would be again be dead, measuring in the 11 V or lower range. Even after needing a jump-start, the battery will start the car again after just 5 minutes of driving.
I've measured the steady-state current draw from the battery after the car has been off for several minutes to several hours using both a clamp-on style ammeter (<0.1 amps; lowest the clamp-on could measure) and an inline current meter between the negative terminal and the negative terminal's clamp (40 mA). 40 mA seems reasonable from what I can find online, and shouldn't be enough to drain the battery over 2 weeks.
So, I have an 11-month old battery that won't hold a charge for two weeks, and I'm fairly confident there's no abnormal current draws from the car. Should I replace the battery again and hope for the best? Is there any truth (and references!) to claims that a lead-acid battery once drained too low can never recover?
Updated with new information for the various suggestions below:
After fully charging the battery, I disconnected it for 48 hours. It remained at 12.6 volts over the entire period, and when I reconnected it, easily started the car.
I don't suspect the alternator: When the car is running, 5-6 amps flows into the battery and the voltage on the battery is 13.6 V; and if I drive the car once or twice a week, the battery never dies.
I do suspect something with the keyless remote. I stopped using my keyless remote years ago because I found it too bulky to carry around -- I lock and unlock the car using the key in the door. Christy still uses her keyless remote. Recently, she was the last one to drive the car before we went out of town for 10 days. When we got back, I was positive the battery would be dead, but it started the car without a problem. So, I ran the experiment of leaving the car unlocked, locked with the key, and locked with the keyless remote. After a few days, the battery would be dead when locked with they key, but not when locked with the keyless remote or left unlocked. Frustratingly, I've checked the current draw in all three configurations, and it's 40 mA in each case (and stays that way for several minutes).
For now, I have a solution that keeps the battery from dying if I don't regularly drive the car, but I'd still like to understand what is going on.
Updated with solution 2010-09-02
At the car's next regular service, the shop recognized the problem. On cars of this type and age, the crimp on the positive terminal can fail turning the positive wire to the battery into a resistor rather than a wire. This is diagnosed by measuring the charging voltage on the battery and giggling the wire (it will jump around, and not remain at the required 13.8 V), and by noticing that the wire itself is hot. Volvo recently released a fix for this, and previously the shop had to remove the entire wiring harness, at great expense, to fix it.
So, my battery was never getting fully charged, and I've selected the best answer from among the suggestions that my measured charging voltage was too low.
At first, I thought the battery was worn out even though it was wasn't quite to the end of its warranty period. I replaced it, but this didn't solve the problem.
Next, I thought our typically short trips weren't allowing the battery to fully charge, so I specifically changed my driving habits and used the trickle charger to top up the battery on a regular basis. After doing this, the battery would measure in the 12.3 to 12.6 V range, but after two weeks without driving would be again be dead, measuring in the 11 V or lower range. Even after needing a jump-start, the battery will start the car again after just 5 minutes of driving.
I've measured the steady-state current draw from the battery after the car has been off for several minutes to several hours using both a clamp-on style ammeter (<0.1 amps; lowest the clamp-on could measure) and an inline current meter between the negative terminal and the negative terminal's clamp (40 mA). 40 mA seems reasonable from what I can find online, and shouldn't be enough to drain the battery over 2 weeks.
So, I have an 11-month old battery that won't hold a charge for two weeks, and I'm fairly confident there's no abnormal current draws from the car. Should I replace the battery again and hope for the best? Is there any truth (and references!) to claims that a lead-acid battery once drained too low can never recover?
Updated with new information for the various suggestions below:
After fully charging the battery, I disconnected it for 48 hours. It remained at 12.6 volts over the entire period, and when I reconnected it, easily started the car.
I don't suspect the alternator: When the car is running, 5-6 amps flows into the battery and the voltage on the battery is 13.6 V; and if I drive the car once or twice a week, the battery never dies.
I do suspect something with the keyless remote. I stopped using my keyless remote years ago because I found it too bulky to carry around -- I lock and unlock the car using the key in the door. Christy still uses her keyless remote. Recently, she was the last one to drive the car before we went out of town for 10 days. When we got back, I was positive the battery would be dead, but it started the car without a problem. So, I ran the experiment of leaving the car unlocked, locked with the key, and locked with the keyless remote. After a few days, the battery would be dead when locked with they key, but not when locked with the keyless remote or left unlocked. Frustratingly, I've checked the current draw in all three configurations, and it's 40 mA in each case (and stays that way for several minutes).
For now, I have a solution that keeps the battery from dying if I don't regularly drive the car, but I'd still like to understand what is going on.
Updated with solution 2010-09-02
At the car's next regular service, the shop recognized the problem. On cars of this type and age, the crimp on the positive terminal can fail turning the positive wire to the battery into a resistor rather than a wire. This is diagnosed by measuring the charging voltage on the battery and giggling the wire (it will jump around, and not remain at the required 13.8 V), and by noticing that the wire itself is hot. Volvo recently released a fix for this, and previously the shop had to remove the entire wiring harness, at great expense, to fix it.
So, my battery was never getting fully charged, and I've selected the best answer from among the suggestions that my measured charging voltage was too low.
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See my updated info in the original question.
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Check your belts, if you have V-belts check for a glazed/ shiny belt ( on side of belt) this will make the belt to slip on higher RPM. Replace if belt is glazed.
Check your belt tension.
Check amp output on alternator, idle and no light, no fan, no air conditioner, no heater it should be about 20 Amps.
Check amp on battery, it is normal to be 5-10 amps, it depends how low the battery is. On very low batteries the amperage could be higher. But if the battery starting to charge the amperage will start to go down after a while if the capacity of the battery increases.
Check for corrosion on the battery post, take the battery connectors off and clean them with a wire brush or sand paper.
Check your Minus wire for corrosion on each end leading from the battery post connector , it will be grounded on the engine, transmission, alternator or bracket ( take the bolts off and clean it).
Also you should have a smaller ground wire that goes from the battery post connector to the fender Check at the fender for corrosion. Or you may have a ground wire that goes from the engine block or transmition to the frame or body, check that for corrosion .
If you have a external voltage regulator, that could be bad also, but that is not to common.
The next 2 things may be checked at the parts store for free. ( autozone, advance auto, etc.)
Have the battery checked, a bad cell in the battery could make the battery have the proper voltage, but the battery could lack on amperage.
Have the alternator checked, a bad alternator could have the proper voltage but could lack on amperage or it could lack on voltage or could lack on voltage and amperage.
Make sure your Engine RPM is right on idle.
13.6 volts is low. The voltage has to be higher so the battery can charge proper.
Check if the voltage goes up if you increase your engine RPM.
Steve
. Disconnect the ground terminal of the battery the next time you plan on being parked for a few days (make sure the battery is fully charged first). If the battery stays charged, you need to start looking for excess load when key is off (you can usually do this by pulling fuses while watching your ammeter and looking for a sudden drop).
. If battery discharges when disconnected, the battery is bad.
.
. Yes, deep discharging a lead-acid battery can damage it. Modern batteries are less prone to this problem, but they are by no means immune.
If the problem is in the car but is an intermittent fault, go and read Zen And The Art Of Motorcycle Maintenance if you haven't already, that's the best primer for intermittent fault finding I can think of :)
It's 1333 by the way!
I also wonder about the possibility of an intermittent fault here, so maybe calibrating the battery's capacity against expectations isn't a bad way to eliminate that question.
But I'm guessing the newer battery has already lost some of its original capacity from general inactivity and accumulated time in a lower state of charge. That's just speaking from experience, and knowing that this sort of usage pattern is what deep cycle batteries were made for surviving over the long term, whereas car battery electrode design assumes they'll almost always be topped off.
Perhaps a DIY solar battery charger project would prevent this problem in the future. :)
There is one thing that will drain a battery quickly even if it is not hooked up to anything at all......it's the plates of the battery.
A short internally, normally causes this. Sometimes there is too much build up from short charges and discharges and two plates (or more) will short out.
With a battery that is not sealed, this was easy to check. You'd get an acide specific gravity tester (a small glass tube with some colored balls inside) and suck up some of the acid....the number of balls floating told you if the cell was charged or not.....a shorted cell, will read discharged or at least MORE discharged then the others.
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. If the OP's battery goes dead while disconnected from the car, that will all but prove your shorted (sulfated) cell(s) theory.
Now, it is impossible to do any "caring" of batteries (thus eliminating harm done by those that didn't care)
I suppose they do last longer now a days, but I have only ever had to replace one battery that I can remember in my life (although, back then, the cars didn't last so long, as I was buying them @ 15+ years old most of the time)
,
Being as it is a 1996 model, and you have changed the most likely cause of the problem (to some, anyway), I'm going to go through some likely scenarios.
1. - Dirt buildup at the alternator where the wire comes out of the alternator. Sometimes, dirt mixed with the natural by-products of use can "bridge" the wire to ground, causing an unusually high discharge/low charge rate.
2. - Have you checked the battery terminals for corrosion? Corrosion causes lack of continuity and can lead to a charging system to not be up to nominal output. Also, do not neglect to check the ground points, as electricity needs to have a return path (but we all know this already, didn't we?). Ground points are sometimes not easy to see, and can easily be forgotten. Add to that the possibility of corroded wires INTERNAL to the sheathing that you see outside the wires. Check all points where there are heavy gauge wire connected to bolts, terminals, and the starter motor.
3. - Have the fusible links checked in the high-amperage lines, as sometimes they tend to not carry the full load (charge) to the system if they have been run to almost rated capacity time after time. How, you ask? Well, the starter is a high-amperage motor with a large current draw. Add to that lights, signals, air conditioning, electric cooling fan, radio, blower motor, etc., and you can picture a wire getting really hot...
4. - Any memory-hold items in the circuits (radio, GPS, etc.) can cause a drain on a battery as well. Perhaps not as much as you think, but still enough to drain a battery after a while. Especially after it not being fully charged. See item No. 2.
5. The fuse block may have dust/dirt/corrosion buildup. The relays may be stuck in the on position draining current through the coils. Have you had problems recently with another / other electrical circuit in the car?
These are some of the quick and dirty items that I can think of off the top of my head, but YMMV depending on what is really going on. This is just some of the armchair quarterbacking from the masses.
Good Luck, Eric.
Check the interior light and the boot and under the hood light actually go off when your parked.
Disconnect the battery lead when not in use 9 does it still go flat in a few weeks.
A fully charged lead acid battery should retain that charge for months with no drain on it.
A "dead" battery can generally be re-lifed however this calls for some special charging equipment - a battery shop should be able to do this for you.
Ogver time or under heavy discharge or deep discharge (under 10.6 volts) a batter is subject to sulphating of the plates which makes it unusable, this can be reversed but calls for a special charging system - see comment above.
I took my old one(s) in to batteries plus and they knew almost immediately what was going on. If you don't keep a charge on car/motorcycle batteries they can go bad. They will often even take a charge but not be able to hold it for more than a few days. I don't know the chemistry behind it but that's what the battery experts had to say.
Also, I have a solar cell I got from a VW dealership that is used for the sole purpose of keeping car batteries charged during shipping from the factory to the dealerships. Dealerships were spending too much money replacing batteries that once drained too low had to be replaced. Seems polychristaline solar chargers with integral charge controllers to keep from overcharging the batteries.
They are considered "disposable" so the consumer rarely if ever sees them. They have a much shorter life than the more expensive monocrystaline cells we see in most applications.
Here's a link to the manufacturer of the solar charging units that explains what I just said but with far more eloquence.
www.icpsolar.com/markets/industrial.html
I'm thinking of a charge-problem like others.
L
I once had a problem with my vehicle identical to what you describe. In my case, it turned out that the trunk was improperly latching, causing the trunk light to remain on at all times. Once I fixed the trunk latch, the problem went away.
Having had similar problems on previous cars I've owned I'm inclined to believe it's the alternator/regulator.
By any chance do you have a Bentley manual? They pay for themselves real quick!
What's the voltage and current while running? Current is going into the battery, right? To me, this sounds like an alternator (or associated componentry) that isn't outputting quite enough current or the voltage is too low and the battery is never getting a full charge (and slowly sulfating).
What is the battery voltage while under load with the car off? If you've got a big power resistor in the lab - throw it on there and remeasure... Or just turn on your high beams (that's about 100+ watts :p). Does the voltage drop significantly? If yes, your battery charge is pretty low.... Fully recharge, and test again - if the voltage drops significantly again - the battery capacity has been damaged from not being fully charged.
Pb Acid batteries are great - but leave them uncharged (or not fully charged) and they slowly sulfate... Overcharge and they gas off. This is why a failed alternator typically takes the battery with it (unless the alternator failed suddenly)
Are the cables clean and tight?
Driving once a week or once in two weeks should be enough to keep the battery charged if the charging system is good, the car starts reasonably easy and there are no extra drains on the battery.
Have your alt. checked for free at pep boys or somewhere like that.
Charge the battery fully then disconnect the ground cable, leave it for two weeks the reconnect the cable and see if it's dead. If it is then the battery is bad. It should hold a charge for months if disconnected. If it is not discharged then there is too much drain in the off position. You could install a disconnect switch but it's a hassle to turn it off and on each time us use the car.
You could run a test by disconnecting one fuse at a time until you find out which circuit is causing the trouble, then working on the items that are on that circuit.
It's hard to isolate a problem like that. I once had a Chev. Monza that I really liked but did the same thing except it only took 3 days. Worked on that car for 6 months. Never did fix it so I just traded it in on something else and made it someone elses problem.
1) something isn't being turned off when the vehicle is disengaged (key off and out). you can check by pulling the battery cable, then use a current meter attached to the now open terminal and the other end attached to the cable.
2) your charging system is failing. A bad diode in the alternator could be the cause, or the regulation circuit could be faulty. Finally, check the drive for the alternator to see if it's slipping.
Other than those, I'm not sure.