Omega Owners Forum

Omega Help Area => Omega Electrical and Audio Help => Topic started by: Auto Addict on 24 May 2011, 10:44:18

Title: Battery Testing
Post by: Auto Addict on 24 May 2011, 10:44:18
I bought a new battery for Mrs AA's Astra last November, been having problems with it, put on charge on my Ring charger, and after 24 hrs it came up with a fault code to say I should replace the battery.

We happened to have a house alarm technician here at the time, and he put it on his battery tester, it read 12.2v 32 amps (it's a 60amp).

Took it back to Lookers this morning, they put it on their battery tester and it came up good battery.

Any ideas where I can go from here?

The tester the house alarm man use was a ACT Intelligent Battery Tester, reatails at about £150.00, brilliant, if expensive, device.
Title: Re: Battery Testing
Post by: Brikhead on 24 May 2011, 11:29:50
I'd check the output from the alternator at the battery leads and also check for current drain with the ignition off, if these prove o.k. then it can only be the battery.

Take it back to Lookers and complain more forcefully!
Title: Re: Battery Testing
Post by: Kevin Wood on 24 May 2011, 12:15:21
Quote
I'd check the output from the alternator at the battery leads and also check for current drain with the ignition off, if these prove o.k. then it can only be the battery.

Take it back to Lookers and complain more forcefully!

Agreed.

Without knowing why the automated tester & charger had a problem with the battery it's hard to advise.

Might be worth an overnight charge on a conventional charger that won't cut out, to establish a known fully-charged condition then try it in the car following my guide:

http://www.omegaowners.com/forum/YaBB.pl?num=1225724099

Then take it back again if it doesn't look good (well discharged this time) ;).

Kevin
Title: Re: Battery Testing
Post by: Auto Addict on 24 May 2011, 16:29:04
Quote
Quote
I'd check the output from the alternator at the battery leads and also check for current drain with the ignition off, if these prove o.k. then it can only be the battery.

Take it back to Lookers and complain more forcefully!

Agreed.

Without knowing why the automated tester & charger had a problem with the battery it's hard to advise.

Might be worth an overnight charge on a conventional charger that won't cut out, to establish a known fully-charged condition then try it in the car following my guide:

http://www.omegaowners.com/forum/YaBB.pl?num=1225724099

Then take it back again if it doesn't look good (well discharged this time) ;).

Kevin

Alternators fine, the spare (old) battery is coping OK on the car, car is charging as it should.

I'm re-charging the new battery as we speak on a conventional charger, and then I'm going to put it on the smart charger.

I'll see what happens then.
Title: Re: Battery Testing
Post by: Kevin Wood on 24 May 2011, 16:33:45
Yep, the thing to try, once it's charged, is whether it settles to a healthy 12.5v+ and whether it holds up with the headlights on for a few minutes.

Kevin
Title: Re: Battery Testing
Post by: Ken T on 24 May 2011, 19:46:04
Quote
I'd check the output from the alternator at the battery leads and also check for current drain with the ignition off, if these prove o.k. then it can only be the battery.

Take it back to Lookers and complain more forcefully!

yes check it on the actual battery posts, with the engine running. After getting a new alternator fitted, my battery was a bit down, and I suspected it was change time, however the battery lead crimp had gone bad and I was loosing a volt or 2 across the bad contact so the battery wasn't getting fully/properly charged.

(http://i159.photobucket.com/albums/t155/lapbits/PICT3850.jpg)

Ken
Title: Re: Battery Testing
Post by: Auto Addict on 25 May 2011, 07:21:54
Quote
Quote
I'd check the output from the alternator at the battery leads and also check for current drain with the ignition off, if these prove o.k. then it can only be the battery.

Take it back to Lookers and complain more forcefully!

yes check it on the actual battery posts, with the engine running. After getting a new alternator fitted, my battery was a bit down, and I suspected it was change time, however the battery lead crimp had gone bad and I was loosing a volt or 2 across the bad contact so the battery wasn't getting fully/properly charged.
http://i159.photobucket.com/albums/t155/lapbits/PICT3850.jpg

Ken

The car if fine, all electrical systems working as they should, no drain on battery, alternator charging as it should.
Title: Re: Battery Testing
Post by: Martian on 25 May 2011, 07:26:06
Quote

The car if fine, all electrical systems working as they should, no drain on battery, alternator charging as it should.
Has to be the battery then, I'd take it elsewhere for a drop test just to get a second opinion before going back to the retailer.
Title: Re: Battery Testing
Post by: Auto Addict on 25 May 2011, 07:42:33
Right, charged it up with a conventional charger, re-charged it with a smart charger.

Both worked OK.

Battery reading 13.3v.

No way of checking how many amps it's holding without investing in an expensive battery tester.

Strange that the battery 'collapsed', and wouldn't charge with the smart charger, but then, (daren't accuse her of this), don't know if Mrs AA has sat there with all the lights on, without the engine running.

Will see how it goes.

Thanks for everyones input :y





Title: Re: Battery Testing
Post by: Kevin Wood on 25 May 2011, 10:00:03
Quote
No way of checking how many amps it's holding without investing in an expensive battery tester.


Amps are a measure of the current that a device is drawing from a  battery, not something that can be measured of the battery itself. ;)

Battery capacity is measured in Amp-Hours (Ah). You can measure that by drawing a current off the battery and measuring how long it takes to discharge.

This is why I suggested testing with the headlights on. A pair of headlights plus sidelights, tail lights, instrument panel lights, etc. probably take about 12-15 Amps. So, an average battery of 60Ah capacity in good condition and fully charged should run that lot for 4 or 5 hours.

Generally, if the battery is poor enough to be causing problems, leaving the headlights on for a few minutes will see it start to flag.

Could be that the battery had been in storage for a long time and was partially sulphated. The smart charger might have timed-out before the battery recovered perhaps?

Kevin
Title: Re: Battery Testing
Post by: Auto Addict on 25 May 2011, 11:58:09
Quote
Quote
No way of checking how many amps it's holding without investing in an expensive battery tester.


Amps are a measure of the current that a device is drawing from a  battery, not something that can be measured of the battery itself. ;)

Battery capacity is measured in Amp-Hours (Ah). You can measure that by drawing a current off the battery and measuring how long it takes to discharge.

This is why I suggested testing with the headlights on. A pair of headlights plus sidelights, tail lights, instrument panel lights, etc. probably take about 12-15 Amps. So, an average battery of 60Ah capacity in good condition and fully charged should run that lot for 4 or 5 hours.

Generally, if the battery is poor enough to be causing problems, leaving the headlights on for a few minutes will see it start to flag.

Could be that the battery had been in storage for a long time and was partially sulphated. The smart charger might have timed-out before the battery recovered perhaps?

Kevin

I meant battery capacity, sorry.
Title: Re: Battery Testing
Post by: Auto Addict on 25 May 2011, 16:32:25
The real good news is it passed it's MOT today with flying colours :y
Title: Re: Battery Testing
Post by: Ken T on 26 May 2011, 08:20:04
When I fixed my terminals the output from the alternator measured at the battery terminals was

(http://i159.photobucket.com/albums/t155/lapbits/PICT3853.jpg)

I don't know if 13.3V is correct or not, but when mine was not charging properly, the terminal volts was around that, which at first glance seemed to be OK. However it kept going flat and struggling to start. Now with the higher volts, a 2 year old battery spins the engine very easily. I wonder if modern batteries need to be kept fully charged up to a high voltage to keep them working at peak efficiency ?.

Ken