Flat battery, causes?
Discussion
Went to use my car last night and it was completely dead, even the remote locking wouldn't work. I bought it 2 months ago and the original owner had just fitted a brand new heavy duty battery, the car is a Mercury Grand Marquis btw, and it has run like a train since.
Started every time and has been fine if left for 2 or 3 days, as I have another car and a bike. This time it had not been driven for at least a week.
Anything obvious I can check, once I have recharged the battery. I have a multimeter but no real idea how to use it or where
as I have only just checked connections in the past.
What voltage should a healthy battery be showing when the engine is running and when the ignition is off and how can I check to see if anything is draining it?
There are no extras on the car that I know of, ie an alarm.
Cheers for any help.
Started every time and has been fine if left for 2 or 3 days, as I have another car and a bike. This time it had not been driven for at least a week.
Anything obvious I can check, once I have recharged the battery. I have a multimeter but no real idea how to use it or where
as I have only just checked connections in the past.What voltage should a healthy battery be showing when the engine is running and when the ignition is off and how can I check to see if anything is draining it?
There are no extras on the car that I know of, ie an alarm.
Cheers for any help.
Went out in a friend's Phaeton on Friday. When we came back to the car, it wouldn't start, with flat battery symptoms (although there was no reason it should have been). We managed to find a guy with a set of jump leads, but as he attached the lead to the positive terminal, it "came off in me 'ands, mate". Positive terminal was loose, completely loose. Tried that?
croyde said:
Went to use my car last night and it was completely dead, even the remote locking wouldn't work. I bought it 2 months ago and the original owner had just fitted a brand new heavy duty battery, the car is a Mercury Grand Marquis btw, and it has run like a train since.
Started every time and has been fine if left for 2 or 3 days, as I have another car and a bike. This time it had not been driven for at least a week.
Anything obvious I can check, once I have recharged the battery. I have a multimeter but no real idea how to use it or where as I have only just checked connections in the past.
What voltage should a healthy battery be showing when the engine is running and when the ignition is off and how can I check to see if anything is draining it?
There are no extras on the car that I know of, ie an alarm.
Cheers for any help.
When running put the test meter across the battery, If it is not showing 13.5-14.4 volts then the alternator is most likely at fault. Otherwise look at current drain. Anything plugged in to the cig lighter, interior lights not dimming, or lastly a leakage somewhere?Started every time and has been fine if left for 2 or 3 days, as I have another car and a bike. This time it had not been driven for at least a week.
Anything obvious I can check, once I have recharged the battery. I have a multimeter but no real idea how to use it or where
as I have only just checked connections in the past.What voltage should a healthy battery be showing when the engine is running and when the ignition is off and how can I check to see if anything is draining it?
There are no extras on the car that I know of, ie an alarm.
Cheers for any help.
And of course could just be the alternator not putting out a charge. There's a million guides on the net on how to check this with a simple multimeter.
As someone who's had both an alternator and dynamo fail to charge the battery on two different cars in the last few months, requiring two separate AA recoveries, this is what I'd be checking first
As someone who's had both an alternator and dynamo fail to charge the battery on two different cars in the last few months, requiring two separate AA recoveries, this is what I'd be checking first
Chicane-UK said:
And of course could just be the alternator not putting out a charge. There's a million guides on the net on how to check this with a simple multimeter.
As someone who's had both an alternator and dynamo fail to charge the battery on two different cars in the last few months, requiring two separate AA recoveries, this is what I'd be checking first
When I submerged the Caterham the regulator failed and it started chucking out 17v. Fried the battery pretty quickly and stank the place out As someone who's had both an alternator and dynamo fail to charge the battery on two different cars in the last few months, requiring two separate AA recoveries, this is what I'd be checking first
What I do and you should never follow my advice just in case..... (usual caveat)
I always check the battery is getting a charge first, some older cars, the ignition lamp is part of the charge circuit so a blown bulb could be an issue, ignition lamp comes on?
Then, as mine is old school (nothing harmed by disconnecting the battery), I put the ammeter in line with the car batter, engine NOT running or the meter is toast, and pull fuses to see when the draw stops.
I did a jump start on our Fiesta and blew its electronic brains out by connecting the jump leads to the battery. Should have earthed to the turbo (it was in the manual but blokes don't read them). Only 700 notes to repair.
I always check the battery is getting a charge first, some older cars, the ignition lamp is part of the charge circuit so a blown bulb could be an issue, ignition lamp comes on?
Then, as mine is old school (nothing harmed by disconnecting the battery), I put the ammeter in line with the car batter, engine NOT running or the meter is toast, and pull fuses to see when the draw stops.
I did a jump start on our Fiesta and blew its electronic brains out by connecting the jump leads to the battery. Should have earthed to the turbo (it was in the manual but blokes don't read them). Only 700 notes to repair.
My Jag does this every so often, there's a sequence that's supposed to happen when you remove the key from the ignition - the steering wheel goes back in and the drivers seat moves backwards. Now and again, that bit doesnt happen, which keeps the circuit open, which drains the battery. It takes a day and a half
It'd be worth checking if anything like that is set, espceially if you have electric seats. Check underneath for the connections, it sounds like something's draining it. The old favourite was always the boot light
It'd be worth checking if anything like that is set, espceially if you have electric seats. Check underneath for the connections, it sounds like something's draining it. The old favourite was always the boot light
I rather sheepishly found our Volvo V70 was not keeping good charge and the AA man showed me that both battery connections were not seated fully. I was not aware that newer terminals are tapered slightly and need to be pushed right down to make a good contact. I had to remove it to jump start another car.
They rather graciously replaced the battery FOC as they assumed it must have been poorly fitted by themselves
They rather graciously replaced the battery FOC as they assumed it must have been poorly fitted by themselves
andy-xr said:
My Jag does this every so often, there's a sequence that's supposed to happen when you remove the key from the ignition - the steering wheel goes back in and the drivers seat moves backwards. Now and again, that bit doesnt happen, which keeps the circuit open, which drains the battery. It takes a day and a half
It'd be worth checking if anything like that is set, espceially if you have electric seats. Check underneath for the connections, it sounds like something's draining it. The old favourite was always the boot light
i had the same with an old car i hadIt'd be worth checking if anything like that is set, espceially if you have electric seats. Check underneath for the connections, it sounds like something's draining it. The old favourite was always the boot light
every now and then the radio display would stop responding (you could still change channels etc) and you couldnt turn the radio off, it would stay on with the car switched off, pressing the off button did nothing
this was ok if you were leaving it for only a few days, but anymore and the cd changer spinning non stop would flatten the battery
after about 15 engine starts it would reset
croyde said:
Just checked and no light switches left on and battery and it's terminals are clean and tight. In fact the engine bay looks almost new. It's a 14 year old car with only 32k miles on the clock and as said, it's a brand new battery.
So how many volts are at the terminals when the engine is off and then running?Just going to check this now.
Got the car going but only by using the jump leads from my 'ol Beemer and jamming an umbrella between the drivers seat and the loud pedal to keep the revs high. Been for a drive and stopped and started it a couple of times with no problems.
The battery is a Yuasa which has a green indicator if charged or black if not. Currently black but the volt meter in my dash has the needle exactly between H and L.
I'll report back.
Got the car going but only by using the jump leads from my 'ol Beemer and jamming an umbrella between the drivers seat and the loud pedal to keep the revs high. Been for a drive and stopped and started it a couple of times with no problems.
The battery is a Yuasa which has a green indicator if charged or black if not. Currently black but the volt meter
in my dash has the needle exactly between H and L.I'll report back.
yonex said:
When running put the test meter across the battery, If it is not showing 13.5-14.4 volts then the alternator is most likely at fault.
Also, once you've re-charged the disconnected battery leave it to stand for a few hours, then check its voltage across the terminals (don't reconnect it). - A "Good" battery should show about 12.6 volts
- Anything less than 12.4 volts and your battery's knackered.
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