Best way to check car battery?
Discussion
Looking for a simple way to check the health of my battery. There's a few on Amazon whereby you connect it to the terminals with the ignition on but engine off, and then take the reading. And then turn the engine on and see what the voltage is at then.
Are these OK to use for a novice who just wants to ensure the battery is running OK every now and again ? Multimeters look quite complicated so I'd rather use one of these.
No signs of poor battery health and I drive lots every day.
Are these OK to use for a novice who just wants to ensure the battery is running OK every now and again ? Multimeters look quite complicated so I'd rather use one of these.
No signs of poor battery health and I drive lots every day.
Those just sound like a voltmeter. They will tell you more about the health of your alternator than they will about your battery.
Unless you are having trouble starting the car and it is turning over slowly or other symptoms of a bad battery then don’t waste your time and money checking it.
A new battery for your Yaris will not be too expensive, save your money and put it towards a new battery (if you ever need one).
Unless you are having trouble starting the car and it is turning over slowly or other symptoms of a bad battery then don’t waste your time and money checking it.
A new battery for your Yaris will not be too expensive, save your money and put it towards a new battery (if you ever need one).
Edited by Scrump on Wednesday 14th September 18:52
Scrump said:
Those just sound like a voltmeter. They will tell you more about the health of your alternator than they will about your battery.
Unless you are having trouble starting the car and it is turning over slowly or other symptoms of a bad battery then don’t waste your time and money checking it.
A new battery for your Yaris will not be too expensive, save your money and put it towards a new battery (if you ever need one).
Yeah I did consider that, thanks Unless you are having trouble starting the car and it is turning over slowly or other symptoms of a bad battery then don’t waste your time and money checking it.
A new battery for your Yaris will not be too expensive, save your money and put it towards a new battery (if you ever need one).
Edited by Scrump on Wednesday 14th September 18:52
Checked how to use the multimeter and seems straightforward ( set it to 20v and then use it as I said above ), those voltmeters seem overpriced due to them looking easier to use and appealing to novices
As you say, I've no symptoms of a bad battery and it is the OEM one so should be fairly decent
The best way is to take the battery to Halfords. They have a fancy machine which can measure how much punch it has.
Of course it would be nice if you then bought your replacement there. Batteries actually aren't that bad in Halfords price wise. I did a bit of detective work earlier in the year and I'm pretty sure they're made by a pretty good brand and seem to be the same spec. Can't remember which brand, might've been Varta or Yuasa.
Of course it would be nice if you then bought your replacement there. Batteries actually aren't that bad in Halfords price wise. I did a bit of detective work earlier in the year and I'm pretty sure they're made by a pretty good brand and seem to be the same spec. Can't remember which brand, might've been Varta or Yuasa.
Piggybacking on this thread with a related question.
At the last service on our A Class (2 ltr petrol), they advised the battery was operating at 62% (or something along those terminology lines). It makes sense it isn't great as the car is 6 years old now and on its original battery.
It gets used most days (16 mile round trip to work).
Question is, should we replace it now before winter? Or is 62% just fine? Batteries aren't that cheap for it!
At the last service on our A Class (2 ltr petrol), they advised the battery was operating at 62% (or something along those terminology lines). It makes sense it isn't great as the car is 6 years old now and on its original battery.
It gets used most days (16 mile round trip to work).
Question is, should we replace it now before winter? Or is 62% just fine? Batteries aren't that cheap for it!
ro250 said:
Piggybacking on this thread with a related question.
At the last service on our A Class (2 ltr petrol), they advised the battery was operating at 62% (or something along those terminology lines). It makes sense it isn't great as the car is 6 years old now and on its original battery.
It gets used most days (16 mile round trip to work).
Question is, should we replace it now before winter? Or is 62% just fine? Batteries aren't that cheap for it!
You will often get 2 figures, state of health and state of charge.At the last service on our A Class (2 ltr petrol), they advised the battery was operating at 62% (or something along those terminology lines). It makes sense it isn't great as the car is 6 years old now and on its original battery.
It gets used most days (16 mile round trip to work).
Question is, should we replace it now before winter? Or is 62% just fine? Batteries aren't that cheap for it!
State of health is usually the ability to store power, so for argument sake lets say its a 500cca battery and its state of health is 50%, its effectively holding 250cca, if its then 50% charged then its even less.
We would usually ask customers if the car struggles to start, if it doesn't then we would just advise to monitor it, if it struggles to start one morning then that's your warning to get it replaced.
ro250 said:
they advised the battery was operating at 62% (or something along those terminology lines)
I expect you'll find that's total bulls
t. There is no test that makes sense to quote at that resolution.Batteries don't last forever and will eventually need replacing but if it's cranking the engine over OK there's no reason to replace it. If it isn't cranking the engine over OK there may be a problem in the charging system, and that might have damaged the battery so it needs replacing after you have fixed the problem, or the battery may just have degraded over time to the point it won't hold a full charge or won't provide the required cranking current. But if it isn't struggling to start the engine there's no reason to mess with it.
Thank you both. It was certainly the state of health he was referring to.
It doesn't struggle to start at all and as it gets used Monday - Friday for albeit only about 8 miles each way, it's probably running for 30 mins each time so it's getting enough time to charge.
It just worries me that it'll decide to not start one cold December morning...
It doesn't struggle to start at all and as it gets used Monday - Friday for albeit only about 8 miles each way, it's probably running for 30 mins each time so it's getting enough time to charge.
It just worries me that it'll decide to not start one cold December morning...
To add my experience.
I would not go the ‘if it’s turning over fine, don’t bother’ route. The battery on my wife’s Fabia was turning over fine for 9 years, then just didn’t. I just clicked and collected a Halfords battery, it was easy to fit. I then checked the Fabia’s handbook and it recommended changing battery every 5 years. Given the cheapness the Fabia has been to run, and its total reliability, the battery cost would be a small price to pay every 5 years (old battery to re-cycling centre).
I would not go the ‘if it’s turning over fine, don’t bother’ route. The battery on my wife’s Fabia was turning over fine for 9 years, then just didn’t. I just clicked and collected a Halfords battery, it was easy to fit. I then checked the Fabia’s handbook and it recommended changing battery every 5 years. Given the cheapness the Fabia has been to run, and its total reliability, the battery cost would be a small price to pay every 5 years (old battery to re-cycling centre).
HustleRussell said:
The best way is to take the battery to Halfords. They have a fancy machine which can measure how much punch it has.
I have (somewhere in the garage) a quite simple gauge that measures CCA (Cold Cranking Amps). I have a couple of V8's that need a fair bit of 'woof' to turn them over and volts don't really tell you that - CCA does.As above
Batteries need load testing, there is no other way of being 100% sure all is good
Proper load testers cost much lolly
Ooooh they're on offer
https://www.arc-components.com/battery-test-equipm...
Wow, cheaper
https://fleetsense.co.uk/durite-heavy-duty-battery...
Batteries need load testing, there is no other way of being 100% sure all is good
Proper load testers cost much lolly
Ooooh they're on offer
https://www.arc-components.com/battery-test-equipm...
Wow, cheaper
https://fleetsense.co.uk/durite-heavy-duty-battery...
In the 40 odd years I have been messing with cars and driving them I have only ever replaced batteries when they stop working. I have never tested a battery just to see if it will be OK this winter. When the battery fails to start the car then test it, a multi-meter will be fine. Check voltage with nothing switched on, should be about 12.7v maybe less if cold. Switch head lights on if it drops below about 8v get a new battery. If it stays above 8v charge it overnight and check again, if when cranking the engine after charging the voltage drops below 8v get a new battery. or jump start it and drive to your local battery supplier and get them to do a test on it.
ARHarh said:
In the 40 odd years I have been messing with cars and driving them I have only ever replaced batteries when they stop working. I have never tested a battery just to see if it will be OK this winter. When the battery fails to start the car then test it, a multi-meter will be fine. Check voltage with nothing switched on, should be about 12.7v maybe less if cold. Switch head lights on if it drops below about 8v get a new battery. If it stays above 8v charge it overnight and check again, if when cranking the engine after charging the voltage drops below 8v get a new battery. or jump start it and drive to your local battery supplier and get them to do a test on it.
InterestingSeveral years ago when I was a lad, 3 x AH capacity discharge for 15 seconds and voltage must stay above 9.6 volts was the test carried out in the battery workshop for lead acid batteries
The technicians in the electrical service garage would do a free test for anyone that wanted one before winter, this saved people from being stuck due to batteries failing when the cold weather arrived
Polly Grigora said:
Several years ago when I was a lad, 3 x AH capacity discharge for 15 seconds and voltage must stay above 9.6 volts was the test carried out in the battery workshop for lead acid batteries
The technicians in the electrical service garage would do a free test for anyone that wanted one before winter, this saved people from being stuck due to batteries failing when the cold weather arrived
This is the right approach. People are taking an old-fashioned view and thinking that "cranking" is everything. It isn't.The technicians in the electrical service garage would do a free test for anyone that wanted one before winter, this saved people from being stuck due to batteries failing when the cold weather arrived
Cranking requires current to turn the heavy engine, but your car's modern electronics need voltage of at least 9 volts to run properly.
A battery needs to be replaced when it's about 50% knackered. There's no point waiting until it lets you down.
And is a £100-£150 battery every five to ten years "expensive"? That's about the same as a tank of petrol these days and a tiny element of total car running costs.
NDA said:
HustleRussell said:
The best way is to take the battery to Halfords. They have a fancy machine which can measure how much punch it has.
I have (somewhere in the garage) a quite simple gauge that measures CCA (Cold Cranking Amps). I have a couple of V8's that need a fair bit of 'woof' to turn them over and volts don't really tell you that - CCA does.SlimJim16v said:
Looks a touch small to apply a 200 amps load for 15 secondsLooks big enough to test a mobile phone battery
My advice is to do what I have done for many years now.
Essentially just use the vehicle and monitor how it turns over when cold. Generally the first time it turns over sluggishly on one of those cold autumn / winter mornings is the time to consider replacement.
Slight caveat. If the battery is some years old then likely a replacement is the option involving least pain and messing about. If the battery is not so old then what use has the vehicle had? Lots of short journeys with a fair bit of electrical in use, lights, wipers, heated rear windscreen and so on can soon mean charge levels drop. In that case an investment into a battery conditioner is handy, both for recovering a discharged battery or giving it a lift in the case of little use / lots of short journeys. I have a Ctek, forgotten how many years now, well into double figures, or a knock off version from such as the middle of Lidl.
Multimeter checks only tell you so much.
Essentially just use the vehicle and monitor how it turns over when cold. Generally the first time it turns over sluggishly on one of those cold autumn / winter mornings is the time to consider replacement.
Slight caveat. If the battery is some years old then likely a replacement is the option involving least pain and messing about. If the battery is not so old then what use has the vehicle had? Lots of short journeys with a fair bit of electrical in use, lights, wipers, heated rear windscreen and so on can soon mean charge levels drop. In that case an investment into a battery conditioner is handy, both for recovering a discharged battery or giving it a lift in the case of little use / lots of short journeys. I have a Ctek, forgotten how many years now, well into double figures, or a knock off version from such as the middle of Lidl.
Multimeter checks only tell you so much.
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