Battery Not Holding Charge!
Discussion
I am having battery problems, seems if I leave the car much more than abut 3 days i don't have enough juice to turn engine over, get rapid clicking. Last time it happened jump started car, no problem. The battery is no more than two years old. Obviously it could just be the battery. I want to check the fuses with ignition off, got my digital multimeter at the ready, the fuse box uses the flat blade type fuses and the probes on my meter wont fit in the slots, is there an easier way to test each of the fuses?
Hate to say it, but could be that the alternator is not charging the battery, as mine presented similar symptoms. Check the voltage across the battery (12.7-12.8 volts when healthy) then fire the car up and test again. When the engine is running, it should be higher, if the alternator is charging the battery. It may simply be that the big fuse is about to die/has died. Give me a shout if I can help.
Steve.
Steve.
Steve_T said:
Hate to say it, but could be that the alternator is not charging the battery, as mine presented similar symptoms. Check the voltage across the battery (12.7-12.8 volts when healthy) then fire the car up and test again. When the engine is running, it should be higher, if the alternator is charging the battery. It may simply be that the big fuse is about to die/has died. Give me a shout if I can help.
Steve.
Thanks Steve, I will investigate the alternator performance, as you suggest, first before before checking all the fuses individually.
I don't think checking the fuses should be your first test.
To charge a 12volt battery, you need to supply it with a voltage that is between 10-20% greater than the battery voltage, in your case 13.2 to 14.4 volts.
I would initially charge the battery with a known working battery charger.
Then with the engine off, meter the battery to make sure you still have 12 volts, if you have, turn on some of the electrics & then re test the battery, this will prove that the battery has the necessary amps aswell (as long as your not drawing more than the battery's capacity e.g. 70ah battery, don't turn on 80ah worth of electrics)
You can test the voltage from the alternator, by starting the engine & re testing the battery, should be between 13.2 & 14.4 volts there.
To test the amps from the alternator, leave the engine running, turn on a few electrics & see if the battery is staying at 13.2 volts or higher.
We've bought a meter from "ACT" for testing batteries, quite pricey though. Most battery suppliers should have a tester of some description, I once bought a battery from a scrap yard, their test involved shorting the pos & neg to see if there was a spark, looking back on this, I'd love to know how he worked at the amps capacity from looking at a spark
To charge a 12volt battery, you need to supply it with a voltage that is between 10-20% greater than the battery voltage, in your case 13.2 to 14.4 volts.
I would initially charge the battery with a known working battery charger.
Then with the engine off, meter the battery to make sure you still have 12 volts, if you have, turn on some of the electrics & then re test the battery, this will prove that the battery has the necessary amps aswell (as long as your not drawing more than the battery's capacity e.g. 70ah battery, don't turn on 80ah worth of electrics)
You can test the voltage from the alternator, by starting the engine & re testing the battery, should be between 13.2 & 14.4 volts there.
To test the amps from the alternator, leave the engine running, turn on a few electrics & see if the battery is staying at 13.2 volts or higher.
We've bought a meter from "ACT" for testing batteries, quite pricey though. Most battery suppliers should have a tester of some description, I once bought a battery from a scrap yard, their test involved shorting the pos & neg to see if there was a spark, looking back on this, I'd love to know how he worked at the amps capacity from looking at a spark
Has the rev counter been playing up?
If you've got a meter measure the volts at the battery as suggested. If you can get around 14V when revving then you have a charge and it's most probably the battery. Could also be an excessive current drain due to simple things like interior lights left on etc.
My money's on it being the big fuse mounted on top of the gearbox bellhousing. You need to remove the fibreglass cover in front of the windscreen, (pull off washer pipes first) and look down between the bulkhead and the rear of the engine.
Open the plastic cover (assuming there's anything left of it) and there should be a flat blade fuse (100A) inside. Use your meter and check for continuity through the fuse. Take care removing the nuts that secure it, use insulated tools or disconnect the battery. Fuse available from most motor factors for around a quid.
If you've got a meter measure the volts at the battery as suggested. If you can get around 14V when revving then you have a charge and it's most probably the battery. Could also be an excessive current drain due to simple things like interior lights left on etc.
My money's on it being the big fuse mounted on top of the gearbox bellhousing. You need to remove the fibreglass cover in front of the windscreen, (pull off washer pipes first) and look down between the bulkhead and the rear of the engine.
Open the plastic cover (assuming there's anything left of it) and there should be a flat blade fuse (100A) inside. Use your meter and check for continuity through the fuse. Take care removing the nuts that secure it, use insulated tools or disconnect the battery. Fuse available from most motor factors for around a quid.
Guys, thanks for the advice, going to have a go now. I have a portable charger pack to jump start her, so will go for a drive then do the tests you guys have suggested. BTW if I have to disconnect the battery will the alarm come on, and if so can I just stop it with the remote fob or do I have to take more drastic action?
For testing the blade fuses in the fuse box, most standard blade fuses have a design which includes two small holes in the plastic so that the voltage across the fuse can be measured with the fuse in situ, and/or a small window which enables you to see whether the fusible element is intact. Assuming you can get reasonable access to the fuse box you should be able to test the fuses in situ. Otherwise you are reduced to pulling them out one by one. Most fuses are difficult to get adequate purchase to pull them out by hand. Various special tools are available to make this easier, but I find a pair of fine nosed pliers works fine.
Sounds to me that you need to charge and test the battery, measure whether the alternator is charging the battery properly, and measure whether there is excessive battery drain when it is switched off.
Sounds to me that you need to charge and test the battery, measure whether the alternator is charging the battery properly, and measure whether there is excessive battery drain when it is switched off.
Just been to the lockup and here's what I found with my nice new digital multimeter...
Flat battery before jump - 8v
After jump start and tickover for a few minutes - 13.8v
Tickover with headlights on - 13.3v
Took it for a drive for 15minutes or so....
Tickover & both fans on - 13.10v
Tickover with lights, aircon fan & cooling fan on - 12.6v
Tickover & just aircon - 13.5v
Engine off - 12.7v
Engine off & lights on - 12.4v
So it sounds like alternator seems to be charging ok?
Checked for current drain next....
Boot light, bulb missing so no drain there.
All interior lights off
Checked fuses for current, meter set to amps, duh! just realised blade fuses have contact points on back (thanks GreenV8s) so put lights on to prove I'm not mad, current showing in fuse no 4, good, lights off and tested all fuses, no current registering at all. So no obvious current drain apart from alarm and imobiliser, so I guess my battery must be fooked, or on the way to being fooked, cant believe just the imobiliser would flaten battery in just 4 days!
Flat battery before jump - 8v
After jump start and tickover for a few minutes - 13.8v
Tickover with headlights on - 13.3v
Took it for a drive for 15minutes or so....
Tickover & both fans on - 13.10v
Tickover with lights, aircon fan & cooling fan on - 12.6v
Tickover & just aircon - 13.5v
Engine off - 12.7v
Engine off & lights on - 12.4v
So it sounds like alternator seems to be charging ok?
Checked for current drain next....
Boot light, bulb missing so no drain there.
All interior lights off
Checked fuses for current, meter set to amps, duh! just realised blade fuses have contact points on back (thanks GreenV8s) so put lights on to prove I'm not mad, current showing in fuse no 4, good, lights off and tested all fuses, no current registering at all. So no obvious current drain apart from alarm and imobiliser, so I guess my battery must be fooked, or on the way to being fooked, cant believe just the imobiliser would flaten battery in just 4 days!
Do you use the car regularly? Batteries don't like long periods between charges, they liked to be kept topped up. Once they go flat then they die quite quickly and need replacing.
If it's only two years old, is it covered by a guarantee? Most decent batteries will be guaranteed for longer than this.
If it's only two years old, is it covered by a guarantee? Most decent batteries will be guaranteed for longer than this.
I'm going for a duff battery, we sell lots at work to go in intruder alarms and we do get the odd one go down with in a year, mainly because we sell cheap crap (Yuasa are the best, but my punters are to tight to pay for em)
Fully charge it on a charger & take it to a battery place, they'll stick a meter on it, the "ACT" meter, checks the temp of the battery, volts & amps (must put it under a load of some description)
City Electrical Factors, sell this meter, give the Dork off the trade counter a couple of quid & he'll probably come & test it for you
Good luck
Fully charge it on a charger & take it to a battery place, they'll stick a meter on it, the "ACT" meter, checks the temp of the battery, volts & amps (must put it under a load of some description)
City Electrical Factors, sell this meter, give the Dork off the trade counter a couple of quid & he'll probably come & test it for you
Good luck
Got the battery out with no problems, however finding a replacement is not so easy, lugged my old battery round about 8 different motor factors in my area, no cigar, anything they have had in stock of correct spec has been, too long, terminals on wrong side (+ terminal needs to line up with opening in fibreglass battery cowling) or not hand clamping lip.
Going to try ARE in Hersham and CPC Batteries in Twickenham, if neither of them can help I will have to attend the Melling gig Sunday with a set of jump leads. If anyone has had any luck finding one for a 4.2 Cerb recently in a 15 mile radius of Kingston Upon Thames please let me know!!!!!
>> Edited by spartacus on Thursday 11th August 17:00
Going to try ARE in Hersham and CPC Batteries in Twickenham, if neither of them can help I will have to attend the Melling gig Sunday with a set of jump leads. If anyone has had any luck finding one for a 4.2 Cerb recently in a 15 mile radius of Kingston Upon Thames please let me know!!!!!
>> Edited by spartacus on Thursday 11th August 17:00
spartacus,
have had similar probs with mine as its not used that often and the alarm/immobiliser drains the battery. this is ok if you keep the car on a trickle charge when not in use. I use a simple plug in 13 amp timer which gives it a 2 hour trickle charge every other day. this certainly helps but have also fitted a battery isolator switch similar to the race cars use which isolates everything including the alarm when not inuse. ok if its in the garage at home but obviously not that safe and secure on the street without the alarm working . I extended the neg battery leads and fitted it bottom right of front , above spoiler - level with front no plate. had similar problems with finding correct battery and gave up in the end and fitted same sixe but with terminals round wrong way - then fitted secondary cables about a foot long with large aircraft type socket on the end which lives on inner wing ready for a jumpstart if needed. had all this for 5 years now and all works well. you can get the aircraft type plug/sockets from demon tweeks i believe.
hope any of this helps. just like you couldnt stop the disscharge from the alarm !!!
have had similar probs with mine as its not used that often and the alarm/immobiliser drains the battery. this is ok if you keep the car on a trickle charge when not in use. I use a simple plug in 13 amp timer which gives it a 2 hour trickle charge every other day. this certainly helps but have also fitted a battery isolator switch similar to the race cars use which isolates everything including the alarm when not inuse. ok if its in the garage at home but obviously not that safe and secure on the street without the alarm working . I extended the neg battery leads and fitted it bottom right of front , above spoiler - level with front no plate. had similar problems with finding correct battery and gave up in the end and fitted same sixe but with terminals round wrong way - then fitted secondary cables about a foot long with large aircraft type socket on the end which lives on inner wing ready for a jumpstart if needed. had all this for 5 years now and all works well. you can get the aircraft type plug/sockets from demon tweeks i believe.
hope any of this helps. just like you couldnt stop the disscharge from the alarm !!!
Gassing Station | French Bred | Top of Page | What's New | My Stuff