After having replaced my battery in a nerve racking ordeal, it occurred to me that I had literally no idea about any of the warning signs until it was far too late. Also, should I have my compressor looked at, they are related I promise.
So let me start by saying that I have a honda accord 2005 lx 4 cld. I live in MA and this winter has been cold. I know that cars don’t really like to start when they are cold so naturally when I turned it on in the cold morning it would take about 6 to 8 revs to turn over. Not a big deal, it has happened for about 3 or 4 months. Apparently not. I had driven it and parked in a garage for about 2 hours and I came back and it would not turn over but all my lights were fine. I called for a jump, drove it hard and fast for about 45 minutes, the next day bought myself a portable jumping unit for myself and my girl friend (it’s valentines day after all and we were in her car), and was going to buy a new battery.
I couldn’t turn on my car again the next morning, so I jumped it with my portable jumper. This led me down a terrifying drive with my engine warning light on, thinking that my alternator was gone and my battery was dead, and I was going to have to wait for a tow to get to sears. It turned out the alternator was fine, but my battery was beyond dead. I think they said it had about 2V left in it. It had so little power left that the dome light would come on but the dash would not.
When I was driving it hard, I tried a few things to see if the battery was okay. After about 15 minutes of driving, I tried the windshield defrost and my dash went dim and the radio turned off. I shut if off, and continued. After about 40 minutes I tried it again and the compressor would actually not cause the dash to flicker, I was pleased. Then I tried the high beams and my car almost stalled. My best guess is that the battery wasn’t providing enough juice to the lights and to the spark plugs and for a brief second the alternator+battery wasn’t pumping enough energy into the system.
So my question is this… how should I have known that my battery was literally on it’s last legs without knowing when it was put in since I got it used? Are there things I should look for, or was it just horrible timing that all of the things that were going wrong with it could have easily been caused by cold weather? How often should I replace my battery and when should I start getting it looked at? Also, my compressor was making my car vibrate such that I can actually feel it but this has been happening for a while now. I know it’s the compressor because it only happens when I have the defrost or AC on. The vibration feels like it’s coming from directly under the dash. I need to get it tuned up anyway, should I have the mechanics look at that too?
Thanks so much.
When I was driving it hard, I tried a few things to see if the battery was okay. After about 15 minutes of driving, I tried the windshield defrost and my dash went dim and the radio turned off. I shut if off, and continued. After about 40 minutes I tried it again and the compressor would actually not cause the dash to flicker, I was pleased. Then I tried the high beams and my car almost stalled. My best guess is that the battery wasn’t providing enough juice to the lights and to the spark plugs and for a brief second the alternator+battery wasn’t pumping enough energy into the system.
It sounds to me like you have an alternator problem, most likely in addition to the battery problem…in fact, the alternator could have caused the battery failure.
The thing is, normal battery voltage is 12VDC or so. Your alternator is supplying 14.5(ish) VDC, at a maximum amperage (not sure what that would be for your car, but it can be readily looked up).
For any modern car, the alternator provides enough amps to run everything on the car, usually even at idle, so the battery is never called upon under normal ops, and could even be removed from the system (though this wouldn’t be kind to the electronic equip, in practice).
The fact that even running the defrost causes a voltage drop (which are the symptoms you desribe) says that you have a very tired alternator, working at a fraction of normal output. In fact, it’s reasonably likely that the battery failed because the alternator simply couldn’t recharge the battery sufficiently from starting the car, at its reduced capacity. Was the test done at idle, or “operating” RPMs?
I’d want to know more specifics re: the testing of the alternator, other than “it’s fine.” How was it tested? How many amps can it output?
If you put a good battery in a car with a bad alternator, you’ll have a bad battery in short time…
Are there still voltage regulators that can go bad? As MJ says the alternator should supply all the power needed, not be drawing on the battery if performing properly. I am still on my 03 battery, though it is getting close to replacement time, - 4 it still starts. It could be bad belt, connections or corrosion at the terminals possibly the battery to ground also.
As I was reading the OP’s post, my first thought was that that the OP’s alternator is on its last legs. Meanjoe has summed up my thoughts precisely.
I concur. Have the alternator tested, most auto parts stores will do this for free.
Step one, stop at your local auto parts store. Most will test the charging system and battery for FREE. They also tend to do a good job. Start there.
I agree with all the above. Have the charging system tested. This test not only load tests the battery, but load tests the alternator. The voltage on the alternator with minimal load may be 14.5V, as normal, but load tested to a 50 AMP draw may drop to 11V, not enough for the electronic control modules like the ECM and BCM.
I’ve seen bad batteries kill alternators in short order. One such job had a battery that seemed to be fine, held 12V, and would start the truck. But, you could literally feel the replacement alternator was overloaded once running. We bench-tested the battery, and it seemed fine, just a little low on CCA. It was low enough to get a warranty replacement, though. I have no idea what broke inside that battery, but replacing it fixed the problem.
" Nerve racking ordeal ", "terrifying drive’ ? The first thing you need to do is calm down. As life goes, a dead battery is small potatoes.
Meanjoe asks the same questions I would ask and gives excellent advice.
I agree it sounds like the alternator.
As for how to tell if battery is good…IF the alternator/charging system is good then a good way to tell if the battery is good is when starting the car on a cold morning. If the engine it turning over good and strong the battery is probably fine. Every battery failure I’ve had the battery started showing signs of weakness when cold (especially when temps get below 0).
So everyone who guessed the alternator was completely correct. I don’t quite know how the people at sears said that it was fine, I took it to my regular mechanic and he pulled it out and had to replace it. It was apparently quite fried. What concerns me about that is that the check engine light never came on. Is that standard for having an almost but not completely fried alternator? I mean, this thing was not producing nearly the output it should have. I am glad to have the ordeal over with though, alas it seems to leave me with more questions.
The terrifying thing isn’t a blown battery, or even loosing an alternator, the nerve racking drive was because if my alternator was gone, and my battery had no charge left, then at any moment my car would stop and not go. This includes merging, at a red light, making a left hand turn in front of oncoming traffic, etc. Basically just a really bad place to be.
Anyway, thanks for everyone’s response, and thanks especially to meanjoe, I think without posting I would have lived in blissful ignorance and my car would have crap out on me and had to buy a brand new battery again.
I am glad you found the problem, but many cars have a battery/volt meter in the dash, does your’s?
What concerns me about that is that the check engine light never came on.
There’s usually also a separate trouble light for the charging system, and they often don’t come on until the alternator output essentially drops to zero.
I am glad you found the problem, but many cars have a battery/volt meter in the dash, does your’s?
What year cars do you drive?? I haven’t seen a car with a meter in 20 years. I haven’t seen a car that even comes with one in 20 years.
Well, Mike, my van is a '96 Dodge but my '99 S10 that I did have and the 2001 company truck that I drove over 200,000 miles had volt meters as well. Where have you been the last 20 years??