Battery Going Completely Dead Overnight Intermittently
Discussion
Hi,
Been quite a while since I last posted, but long time lurker. Hoping someone might have some ideas, as pretty much pulling my hair out with it.
We have a 2014 Ford Kuga MK2, that we've owned for around 2 years. Approximately 6 months after we bought it, had symptoms of battery coming to the end of it's life, with random dash lights flickering and such so replaced it with a Bosch S5; all issues resolved.
Cue two weeks ago, went out to start the car on Sunday afternoon, and neither fobs worked - the car had been drove home Saturday night from a restaurant so approximately 14 hours of being off. Had to use the key within the fob to open, and no lights or anything on the inside of the car. Checked the battery and it's at 6.7V.
Removed the battery, which is a bit of a pain on the Kuga having to take the airbox off each time, trickle charged it to full and refitted. Car worked fine for 2 weeks without issue, checked to make sure the battery was charging whilst the engine was running and such. However come last Saturday morning and the car is completely dead again, reading 6.7V.
I've taken the battery out, trickle charged it and popped it back in again. Checked the amp draw with a clamp straight away and was showing 20-30mA, unlocked and locked the car - 20 minutes later it's showing as settling back to 20-30mA range. Then I've taken it on a drive, used just about everything possible that's electric in the car, waited 30 minutes after getting home for everything to go to sleep, and it's all good with a 20-30mA draw.
So, seems it has a very intermittent, but absolutely huge parasitic draw when it happens to drop the battery so fast. But where do I go from here in trying to get this sorted without being able to replicate it? I know these things can be a pain to find at the best of times.
Thanks for any help
Been quite a while since I last posted, but long time lurker. Hoping someone might have some ideas, as pretty much pulling my hair out with it.
We have a 2014 Ford Kuga MK2, that we've owned for around 2 years. Approximately 6 months after we bought it, had symptoms of battery coming to the end of it's life, with random dash lights flickering and such so replaced it with a Bosch S5; all issues resolved.
Cue two weeks ago, went out to start the car on Sunday afternoon, and neither fobs worked - the car had been drove home Saturday night from a restaurant so approximately 14 hours of being off. Had to use the key within the fob to open, and no lights or anything on the inside of the car. Checked the battery and it's at 6.7V.
Removed the battery, which is a bit of a pain on the Kuga having to take the airbox off each time, trickle charged it to full and refitted. Car worked fine for 2 weeks without issue, checked to make sure the battery was charging whilst the engine was running and such. However come last Saturday morning and the car is completely dead again, reading 6.7V.
I've taken the battery out, trickle charged it and popped it back in again. Checked the amp draw with a clamp straight away and was showing 20-30mA, unlocked and locked the car - 20 minutes later it's showing as settling back to 20-30mA range. Then I've taken it on a drive, used just about everything possible that's electric in the car, waited 30 minutes after getting home for everything to go to sleep, and it's all good with a 20-30mA draw.
So, seems it has a very intermittent, but absolutely huge parasitic draw when it happens to drop the battery so fast. But where do I go from here in trying to get this sorted without being able to replicate it? I know these things can be a pain to find at the best of times.
Thanks for any help
The current (18 month old replacement) battery could have developed a fault. Have you been able to test it? Given the complexity of electronic fault-finding, buying a new battery could be worthwhile as it would at least eliminate that as a suspicion.
I think I "fixed" a battery drain on my 2007 Merc by removing the CD multi-changer, and I got that idea from someone else on here who'd had the same, so that might be worth a try. I'm afraid I don't have any other great tips for the actual issue!
In the meantime you could get a CTEK battery charger since they come with a 'tail' that you can leave permanently connected to the battery, saving the hassle of removing the airbox each time. You could also get one of the portable jump-start devices to keep in the glovebox, to mitigate the risk of returning to the car in a car park and being unable to get home, if you don't have one already - they're surprisingly small and effective nowadays.
I think I "fixed" a battery drain on my 2007 Merc by removing the CD multi-changer, and I got that idea from someone else on here who'd had the same, so that might be worth a try. I'm afraid I don't have any other great tips for the actual issue!
In the meantime you could get a CTEK battery charger since they come with a 'tail' that you can leave permanently connected to the battery, saving the hassle of removing the airbox each time. You could also get one of the portable jump-start devices to keep in the glovebox, to mitigate the risk of returning to the car in a car park and being unable to get home, if you don't have one already - they're surprisingly small and effective nowadays.
I had similar issue with a Honda that took me years to track down. I kept a solar maintainer on it but every now and again it'd just be completely dead.
I tried all sorts of things - a new battery of course, then switching certain things off, taking fuses out, leaving it locked, unlocked, and rigging up a multimeter to try and figure out how much power everything used. Nothing worked.
Eventually I took it to Honda. They plugged in a laptop, installed a software update, asked for £100 and that was the problem solved
I tried all sorts of things - a new battery of course, then switching certain things off, taking fuses out, leaving it locked, unlocked, and rigging up a multimeter to try and figure out how much power everything used. Nothing worked.
Eventually I took it to Honda. They plugged in a laptop, installed a software update, asked for £100 and that was the problem solved
Dud battery? I took mine in and a cell had gone so got a replacement (euro car parts)
Maybe battery sat for a long time on shelf. Unlikely
Faulty alternator? Thus killing old battery and now rapidly killing new battery (car running on battery whilst driving)
Or like others said some strange draw from the car
Maybe battery sat for a long time on shelf. Unlikely
Faulty alternator? Thus killing old battery and now rapidly killing new battery (car running on battery whilst driving)
Or like others said some strange draw from the car
If the battery has got down to 6.7v then it's Fubared. You can temporarily breath life back into it with a charger, but that's just delaying the inevitable. 20-30mA is a pefectly normal drain on a modern car.
The only question in my mind is how it got to 6.7v first time round - was that zero use over lockdown or through a very cold winter, or was that during normal use when you would expect it to stay charged?
The only question in my mind is how it got to 6.7v first time round - was that zero use over lockdown or through a very cold winter, or was that during normal use when you would expect it to stay charged?
Quite a few questions but appreciate the help!
No the car battery went from fully charged to 6.7V in 14 hours.
Many Thanks
Bobtherallyfan said:
Had a similar problem with a CRV…turned out to be the air con relay was sticking on live and draining the battery totally even though the engine was switched off.
Yeah I was hoping it was a relay that was staying on, but checking the amp draw for 30mins didn't show anything even intermittently coming on/off.samoht said:
The current (18 month old replacement) battery could have developed a fault. Have you been able to test it? Given the complexity of electronic fault-finding, buying a new battery could be worthwhile as it would at least eliminate that as a suspicion.
Thanks, I'll give euro a call in the morning, seeing as it has a 5 year warranty, and possibly ask if I can bring it in for them to test.blank said:
What clamp are you using? Very few are accurate when reading 20-30mA.
In all honesty it's a cheap no name one, but it does the job in the sense it goes between 20-40mA, it's certainly not showing anything like 500+mA which I would suspect it would be if it's draining the car battery from full to 6.7A in 14 hours.Mave said:
If the battery has got down to 6.7v then it's Fubared. You can temporarily breath life back into it with a charger, but that's just delaying the inevitable. 20-30mA is a pefectly normal drain on a modern car.
The only question in my mind is how it got to 6.7v first time round - was that zero use over lockdown or through a very cold winter, or was that during normal use when you would expect it to stay charged?
So if the battery has gone down to 6.7V twice then it's caused irreversible damage to the battery? Yeah 20-30mA is fine, I has suspected if it was a constant parasitic drain it would be considerably more.The only question in my mind is how it got to 6.7v first time round - was that zero use over lockdown or through a very cold winter, or was that during normal use when you would expect it to stay charged?
No the car battery went from fully charged to 6.7V in 14 hours.
Many Thanks
Greengecko said:
No the car battery went from fully charged to 6.7V in 14 hours.
That suggests something like a 5 amp draw, assuming it's consistent. Which means something is dissipating about 60 Watts of heat. You should be able to find what this at time of year - it should be quite warmAs was said by A.N.Other poster above the battery is goosed.
It was clearly on its last legs & when it went flat as you described was it's final death rattle.
Batteries very rarely recover when they get that flat, the draw you are seeing is just fine, the battery capacity is probably 20/30% of what it should be so it will just go flat again quicker than the current draw suggests.
Replace it & it will be fine.
It was clearly on its last legs & when it went flat as you described was it's final death rattle.
Batteries very rarely recover when they get that flat, the draw you are seeing is just fine, the battery capacity is probably 20/30% of what it should be so it will just go flat again quicker than the current draw suggests.
Replace it & it will be fine.
But, but, but the OP hasn't commented that it took 14 hours to drop the battery voltage to 6.7 volts
OP comments that the battery was at 6.7 Volts 14 hours later
Battery could have dropped to 6.7 Volts at any time during those 14 hours
Doubt very much that the OP did without sleepy time to check battery voltage every hour
Yes the fault is a proper pain if an intermittent current draw is causing the problem
OP - Don't ditch the battery, recharge the battery and have it discharge tested once it has cooled down over several hours
OP comments that the battery was at 6.7 Volts 14 hours later
Battery could have dropped to 6.7 Volts at any time during those 14 hours
Doubt very much that the OP did without sleepy time to check battery voltage every hour
Yes the fault is a proper pain if an intermittent current draw is causing the problem
OP - Don't ditch the battery, recharge the battery and have it discharge tested once it has cooled down over several hours
Greengecko said:
... drove home Saturday night from a restaurant
How far was that? Have you been using the car much since Covid?Daughter had this on her car but it transpired that working from home all she was doing was very short journeys to take kids to school - just a tad too long to walk with little kids - and go shopping.
She was having the same thing as you describe - jump start the car, take if for an hour round trip and it'd be OK for a couple weeks, then dead again.
The car's average journey was about a mile and, more crucially, only a few mins run time - it's run time that charges the battery more than distance as modern charging systems do little more than float charge the battery.
Penelope Stopit said:
Battery could have dropped to 6.7 Volts at any time during those 14 hours
OP - Don't ditch the battery, recharge the battery and have it discharge tested once it has cooled down over several hours
Both very valid points, yes get it tested after a full charge & a min with lights on to remove the surface charge, but it will quite likely come back as shot.OP - Don't ditch the battery, recharge the battery and have it discharge tested once it has cooled down over several hours
bolide said:
That suggests something like a 5 amp draw, assuming it's consistent. Which means something is dissipating about 60 Watts of heat. You should be able to find what this at time of year - it should be quite warm
Thanks for the calculation and reply, I do suspect it's draining a lot quicker than over the 14 hours, so my guess would be that it's disspiating even more heat than that!Penelope Stopit said:
But, but, but the OP hasn't commented that it took 14 hours to drop the battery voltage to 6.7 volts
OP comments that the battery was at 6.7 Volts 14 hours later
Battery could have dropped to 6.7 Volts at any time during those 14 hours
Doubt very much that the OP did without sleepy time to check battery voltage every hour
Yes the fault is a proper pain if an intermittent current draw is causing the problem
OP - Don't ditch the battery, recharge the battery and have it discharge tested once it has cooled down over several hours
Yeah you're right, I have no idea if it happened over the 14 hours, or over 3 hours for example. OP comments that the battery was at 6.7 Volts 14 hours later
Battery could have dropped to 6.7 Volts at any time during those 14 hours
Doubt very much that the OP did without sleepy time to check battery voltage every hour
Yes the fault is a proper pain if an intermittent current draw is causing the problem
OP - Don't ditch the battery, recharge the battery and have it discharge tested once it has cooled down over several hours
I checked it last night at 12.5V before bed, this morning it was at 12.15V and more than enough to start the car.
Going to look at getting it tested, part of me thinks it is some huge intermittent parasitic draw, rather than the battery itself though.
Sheepshanks said:
How far was that? Have you been using the car much since Covid?
Daughter had this on her car but it transpired that working from home all she was doing was very short journeys to take kids to school - just a tad too long to walk with little kids - and go shopping.
She was having the same thing as you describe - jump start the car, take if for an hour round trip and it'd be OK for a couple weeks, then dead again.
The car's average journey was about a mile and, more crucially, only a few mins run time - it's run time that charges the battery more than distance as modern charging systems do little more than float charge the battery.
It was around an hour trip home, so plenty enough. Other half works in a school that is around a 30 minute drive each way, so has been used consistently, at least for the past 6+ months.Daughter had this on her car but it transpired that working from home all she was doing was very short journeys to take kids to school - just a tad too long to walk with little kids - and go shopping.
She was having the same thing as you describe - jump start the car, take if for an hour round trip and it'd be OK for a couple weeks, then dead again.
The car's average journey was about a mile and, more crucially, only a few mins run time - it's run time that charges the battery more than distance as modern charging systems do little more than float charge the battery.
Appreciate you taking the time to pop a suggestion in though
You need to track down the cause of the current drain. You can do that with a good digital voltmeter by measuring the voltage drop across each fuse and looking up the corresponding current for that fuse type. I suspect you'll find it's a sticking relay, faulty door switch or something of that sort.
Car batteries are not designed for a deep discharge. A battery that has dropped below 12V will have been damaged by that. By the time you've got down to 6V you've completely flattened at least three cells. Even once could be enough to render the battery unusable, and doing it multiple times makes that even more likely. At best, the battery will have compromised current and charge capacity. Plan to replace the battery after you have resolved the current drain and confirmed the charging system is working properly.
Car batteries are not designed for a deep discharge. A battery that has dropped below 12V will have been damaged by that. By the time you've got down to 6V you've completely flattened at least three cells. Even once could be enough to render the battery unusable, and doing it multiple times makes that even more likely. At best, the battery will have compromised current and charge capacity. Plan to replace the battery after you have resolved the current drain and confirmed the charging system is working properly.
Recently I installed one of these to deal with a battery drain problem that I couldn't trace.
There are loads to choose from.
https://www.durite.co.uk/s/c/switches-and-indicato...
I went for this one:
https://www.durite.co.uk/ItemDetails/ItemDetails.a...
It's discreetly located above the bonnet and below the windscreen, near the base of the wipers. I just turn it off when I park the car after I've locked it. Problem solved.
ETA:
The starter motor isn't powered through this, but everything else is.
There are loads to choose from.
https://www.durite.co.uk/s/c/switches-and-indicato...
I went for this one:
https://www.durite.co.uk/ItemDetails/ItemDetails.a...
It's discreetly located above the bonnet and below the windscreen, near the base of the wipers. I just turn it off when I park the car after I've locked it. Problem solved.
ETA:
The starter motor isn't powered through this, but everything else is.
Edited by Bennet on Tuesday 16th November 11:57
Greengecko said:
I checked it last night at 12.5V before bed, this morning it was at 12.15V and more than enough to start the car.
Going to look at getting it tested, part of me thinks it is some huge intermittent parasitic draw, rather than the battery itself though.
12.15 volts is around 20/25% of capacity remaining, if you have still had just 20/30ma drain overnight after having 12.5 volts (80% charged) when you switched it off the battery will be stuffed.Going to look at getting it tested, part of me thinks it is some huge intermittent parasitic draw, rather than the battery itself though.
Never ever given something like this a thought until now
Using a length of twin cable that will reach from car to bedroom
Use battery monitor to wake you up if there's a drop in car battery voltage, alarm trigger voltage can be adjusted
Leave ammeter connected to battery post and its cable, connect battery monitor and get tucked in for a possible bad nights sleep
When battery drain is high, voltage drops, alarm sounds in bedroom
Get out of bed, run out to vehicle and take a look at how much drain is showing on the ammeter
https://www.amazon.com/Battery-Monitor-Voltage-Dis...
Could be good innit
Using a length of twin cable that will reach from car to bedroom
Use battery monitor to wake you up if there's a drop in car battery voltage, alarm trigger voltage can be adjusted
Leave ammeter connected to battery post and its cable, connect battery monitor and get tucked in for a possible bad nights sleep
When battery drain is high, voltage drops, alarm sounds in bedroom
Get out of bed, run out to vehicle and take a look at how much drain is showing on the ammeter
https://www.amazon.com/Battery-Monitor-Voltage-Dis...
Could be good innit
I looked but couldn't see OP mention it (so apologies if I'm being blind) but, have you checked the voltage when the engine is running? I'm just wondering if the alternator or charging circuitry is kaput. Should be around 14V with the engine running.
As OP has a clamp meter I'm assuming he has a more than decent multimeter, if not does the Kuga show battery voltage in a hidden diagnostic menu?
As OP has a clamp meter I'm assuming he has a more than decent multimeter, if not does the Kuga show battery voltage in a hidden diagnostic menu?
Gassing Station | Home Mechanics | Top of Page | What's New | My Stuff