Possible Battery drain
Discussion
Even fully charged, the battery wil lose power over a two or three day period to the point where the car won't start.
Now it may be coincidence BUT it all started to happen after a certain well known accessory store fitted new all singing all dancing audio unit.
So I could disconnect the battery and see if it still loses charge but how do I determine where it's draining?
Even if I disconnect the battery I suppose it could be the battery itself although when I bought the car I was told it was a new one (year ago)?
I have a multi meter just not sure how to use it!
Now it may be coincidence BUT it all started to happen after a certain well known accessory store fitted new all singing all dancing audio unit.
So I could disconnect the battery and see if it still loses charge but how do I determine where it's draining?
Even if I disconnect the battery I suppose it could be the battery itself although when I bought the car I was told it was a new one (year ago)?
I have a multi meter just not sure how to use it!
RR-B fixer said:
Try this... Disconnect the negative cable from the battery. Set your multimeter to Amps. Connect one lead to your battery negative terminal, and the other to the cable you just removed (i.e. re-connecting / completing the circuit). Now read the Amps on your multimeter. That reading is what your car is draining from your battery. Check all your interior lamps are off (common fault / mistake). Generally, it's common for a car to drain 0.05ish Amps. Look for no more than this. If you have more, start pulling out fuses (start with new stereo) and checking multimeter one by one. Remember though... Do not turn ignition on or attempt to start car with battery cable disconnected as you will damage your multimeter! Good luck! Let us know how you get on...
Thanks for the clear instructions, will do this over the weekend (after freeing off a rear brake).AW10 said:
You probably won't permanently damage the multimeter by running too much current through it - just blow the fuse within it.
Does the radio work with the ignition off and the key out? If yes it may be wired to a permanent live rather than a switched live.
Boot and glovebox lamps can fail to switch off - one way to find them is to use a smartphone with a video record feature and put it in the boot/gloxebox to ensure the light goes out.
And what sort of car is it? Many new cars "go to sleep" to reduce battery consumption but if something is wired wrong the car won't go into sleep mode and the battery will drain rapidly.
Will look after the MMDoes the radio work with the ignition off and the key out? If yes it may be wired to a permanent live rather than a switched live.
Boot and glovebox lamps can fail to switch off - one way to find them is to use a smartphone with a video record feature and put it in the boot/gloxebox to ensure the light goes out.
And what sort of car is it? Many new cars "go to sleep" to reduce battery consumption but if something is wired wrong the car won't go into sleep mode and the battery will drain rapidly.
Radio off when key out BUT it has a memory for the clock, stations I presume, Bluetooth etc (Screen blank though)
Def not the boot area, will check glovebox.Could be but I think that would drain it quicker. Usually ok overnight, it's when left for a couple of days
Volvo 940 Estate
Thanks
Well tried the disconnect and multimeter - nothing obvious there, except when I reconnected the battery and came to reset up the audio unit I had a hell of a trouble getting my phone Bluetooth thing to pair but that's probably just me being old and not understanding these modern things.
Last player used cassettes.....
Last player used cassettes.....
PositronicRay said:
Get the battery checked.
It has 12.5V across the terminals but that's not to say it isn't eating itself inside. It's a Varta and when I bought the car 10 months ago it was apparently new, but I cannot see a date on it.Still think it's strange that this only started after the new radio was fitted - coincidence maybe
Haven't gone away, or rather I did, holiday in the Volvo.
long journeys charge the battery and the car spins over fast but after a couple of days of shorter journeys and the laddie leaving a door open ocassionally and the car refused to start.
TBH I'm beginning to think it's either the battery or the alternator putting the light out but not charging very much.
Further tests to come now I'm back home.
long journeys charge the battery and the car spins over fast but after a couple of days of shorter journeys and the laddie leaving a door open ocassionally and the car refused to start.
TBH I'm beginning to think it's either the battery or the alternator putting the light out but not charging very much.
Further tests to come now I'm back home.
Well it's not the alternator, or I've got two dodgy ones.
One problem I seem to have is the belt (new) keeps working slack.
But car fully charged with a charger, two 6 mile trips per day plus a couple of 10 milers over the weekend and it was dead this morning. Jump start from pack, 6 miles to work, bump on a slope this evening and it spun over quickly when I got home. Now on a charger though.
Beginning to think its just a knackered battery.
One problem I seem to have is the belt (new) keeps working slack.
But car fully charged with a charger, two 6 mile trips per day plus a couple of 10 milers over the weekend and it was dead this morning. Jump start from pack, 6 miles to work, bump on a slope this evening and it spun over quickly when I got home. Now on a charger though.
Beginning to think its just a knackered battery.
SebringMan said:
Does your HU turn off with the ignition or not?
What car is it and what HU?
I'd check the drain on the car myself if it is going flat in a few days, it will have to be a hefty drain to flatten the battery that much.
HU - head unit?What car is it and what HU?
I'd check the drain on the car myself if it is going flat in a few days, it will have to be a hefty drain to flatten the battery that much.
Yes but I'm also switching it off.
Must have a permanent live though as it has a memory for the stations
Garybee said:
You're changing components you haven't tested and ignoring people who are giving you the information you need to find the problem in minutes. I'd suggest that you just call an auto electrician at this point. It'll cost you less than your current approach.
Not cost me anything so far as the alternator was sitting in my garage.Car now fully charged, will try and leave it a few days with the battery disconnected and see where I stand. It's just a right pain resetting the radio unit again from scratch.
And yes will recheck the battery drop while I'm on.
Garybee said:
Find the fuse for the radio and measure the voltage across it. Leave everything connected and the fuse in place. If you are not sure how to do this post a picture of your multimeter and I will guide you.
The fuse, a blade type is hidden in the fuse box behind the ash tray in the centre console. It's easy to see, reasonably easy to pull a fuse out with the supplied tweezers but a pain to get to multimeter leads to. But i'll have a go at the weekend.Well auto electrician it has to be....
Car has been fine for a fortnight, even left standing for a couple of days it spun over like old times.
Used it yesterday, two 10 mile trips. Was beginning to think whatever was wrong had fixed itself.
Went to it this afternoon and dead again.
Jumper pack started at front door.
10 mile trip, left 10 minutes and wouldn't start again, even battery pack failed this time.
Car has been fine for a fortnight, even left standing for a couple of days it spun over like old times.
Used it yesterday, two 10 mile trips. Was beginning to think whatever was wrong had fixed itself.
Went to it this afternoon and dead again.
Jumper pack started at front door.
10 mile trip, left 10 minutes and wouldn't start again, even battery pack failed this time.
Well, into Halfords:
Oh we've had this before.......
The drain via the radio fuse was 0.08. He then took the supply from another fuse on the fusebox, drain dropped to 0.01 or less.
Now don't ask me to explain this, he tried and failed, but so far everything seems fine. Only thing I find is that the unit doesn't work on the first turn of the key (aux?)
Oh we've had this before.......
The drain via the radio fuse was 0.08. He then took the supply from another fuse on the fusebox, drain dropped to 0.01 or less.
Now don't ask me to explain this, he tried and failed, but so far everything seems fine. Only thing I find is that the unit doesn't work on the first turn of the key (aux?)
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