Starter battery voltage
- Thread starter t0mb0
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When using your mains charger are you putting the negative onto the battery terminal or the van body?
Van body,
Lidl charger has longer span leads so I was able to attach negative lead to the earth point which is on drivers side of the engine, as Ctec charger leads have really short span hence it would not be able to reach that point. Just unplugged the charger and it's showing 12.7 on my multimeter.
Lidl charger has longer span leads so I was able to attach negative lead to the earth point which is on drivers side of the engine, as Ctec charger leads have really short span hence it would not be able to reach that point. Just unplugged the charger and it's showing 12.7 on my multimeter.
Alan Spencer
Member
Hi All ! I am just getting acquainted with my VW's electrics. I put the vans own battery on charge yesterday as, although it is a new vehicle it has been standing on a forecourt for a little while and only taking short trips into the workshop. I charged it with my Cetek CT5 charger and it was on charge from 11am until 6pm it got to 13.5 and I was waiting for the charger to swap over to "Care" but it didn't do that so I took it off charge in case I damaged the battery. The Charger has only been used about 5 times to Charge my Fiesta ST Line's battery and there has been no problems with switching over to "Care" then. Any ideas guys ? Do you think I took it off charge to early ? Alan.
Overnight for mine. Just leave it on.
As Cab said, leave it for longer. I have Ctek 3.8 and I leave it plugged in, in my campervan when not in use now the weather is bit iffy. Float takes sometimes 2-3 days (level 6) to appear if cold as now, and then pulse charge (level 7) after a week or so.
Alan Spencer
Member
Hi EdH ! I don't know what you are referring to as regards Level 6 & 7, I guess it is stages on your particular Ctek charger but as you say, I'll do what Cab says, I will give it longer.
Yes, charge levels.
I am monitoring my battery due to engine management light on and multiple error codes shown…
First reading was 12V after a cold night, cranking was difficult that morning.
I have then charged the battery overnight and it showed 14.5 before disconnecting c-tek.
After disconnection showing 12.7V.
Back in the car, cranking perfectly. Drove it for one hour. Back to the van one hour later battery level 12V.
Had the van 8 months now, don’t know how old is the battery. It seems the original battery from Factory.
Decided to get a new Battery, Yuasa 9000.
I’ll let you know the readings when new and after driving it.
First reading was 12V after a cold night, cranking was difficult that morning.
I have then charged the battery overnight and it showed 14.5 before disconnecting c-tek.
After disconnection showing 12.7V.
Back in the car, cranking perfectly. Drove it for one hour. Back to the van one hour later battery level 12V.
Had the van 8 months now, don’t know how old is the battery. It seems the original battery from Factory.
Decided to get a new Battery, Yuasa 9000.
I’ll let you know the readings when new and after driving it.
On "smart-charger" that would indicate the battery is still drawing significant current (possibly even the max the charger can provide - still at "Bulk-charge") - thus battery is nowhere near full... or faulty...was the battery warmer than the ambient?
I thought I had asked questions about starter battery voltage a couple of years but could find them via a search so I'll try again. I've never seen particularly convinced by the OEM battery in my van (a Varta EFB+ 70Ah) - although it's never actually let me down, it does sometimes seem to 'hesitate' before actually starting the van. In the summer and parked on the drive at home, it's not a real problem as the solar panel on the roof keeps the leisure system topped up and then trickles into the starter but it's obviously a different story in the winter or when the van is parked in shade - on one occasion when we were in Croatia last year and parked under trees, I went to start it for the first time in 6 days and for a brief time, I didn't think it was going to make it. When at home, if I leave the van on the drive for any longer than a week, I tend to plug in a Ctek MX5 charger for a couple of days but even then, the charge in the battery rarely exceeds 12.7V and after a day or so, it sits at 12.4V a couple odd days after being unplugged but as soon as I unlock and the 'systems' start up, the drops to 12.2 V or lower. Whenever it's locked and parked, I never let it go down too far just in case. Is this normal?
Mine is exactly the same, I am beginning to think that the ‘device’ on the neg terminal stops the battery going over 12.5 even when on charge through the cig socket using external charger.
also I should add that the voltage drop when unlocking is brief as I understand it also triggers all sorts of things to run (pumps, heater) in anticipation of you starting the vehicle but after a few mins of inactivity they shutdown and the voltage returns to 12.5.
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How old is the battery ?
Dropping to 12.2v when you unlock and get ready to start is fairly normal for an old-ish battery. You should certainly be able to go more than 6 days, but if you unlocked and locked the van multiple times, interior lights came on etc in those 6 days, then that will drain the battery.
Pete
@Nigel, Do you know what the 'device' actually is" I googled the part number (7EO915181K on my 2018 van but it doesn't turn up any description other than something vague like 'Negative Battery Lead'.
@Pete C. It's the original battery from a 2018 van. It might well last more than a week when unused but I don't fancy chancing it much longer. The van might be locked/unlocked a few times but I've got the courtesy lights all switched off. As I said, I thought that I had posted about this before and I can't the post but as far as I can recall, the numbers were't much different 3 years ago. I've also got an 2014 Audi Q5 which is getting on a bit now but I do know that it's still on the original battery as I've had the car from less than a year old and I've got no such worries about the battery. Sorry, I don't know the battery size but it was left untouched for 6 weeks last September/October and stated immediately when I pushed the key in.
Back to the van, maybe I've just go to stop putting off a new battery and order one in. The only valid excuse so far has been that I'm too lazy to sort it out but I don't want to do it if it's unnecessary - the last thing the world needs is another large battery needing to be disposed of.
@Pete C. It's the original battery from a 2018 van. It might well last more than a week when unused but I don't fancy chancing it much longer. The van might be locked/unlocked a few times but I've got the courtesy lights all switched off. As I said, I thought that I had posted about this before and I can't the post but as far as I can recall, the numbers were't much different 3 years ago. I've also got an 2014 Audi Q5 which is getting on a bit now but I do know that it's still on the original battery as I've had the car from less than a year old and I've got no such worries about the battery. Sorry, I don't know the battery size but it was left untouched for 6 weeks last September/October and stated immediately when I pushed the key in.
Back to the van, maybe I've just go to stop putting off a new battery and order one in. The only valid excuse so far has been that I'm too lazy to sort it out but I don't want to do it if it's unnecessary - the last thing the world needs is another large battery needing to be disposed of.
Now I’m no expert but from reading on this forum I understand that there is a device on the negative terminal of the battery which monitors it and ensures that it does not charge over 80% so that there is always room for the regenerative braking.
That is why absolutely nothing should ever be connected directly to this terminal.
Alan Spencer
Member
Well done Nigel W ! I think that is the most logical answer we have received. That probably answers my query about the fact that my battery has been on charge for 8 hrs and the Cetek charger won't flick in to "Care" mode the battery is showing 13.5 and it doesn't seem to want to take any more charge. I think it's time to consult Marshalls VW but I am almost sure you have the answer right there which seems logical ! My van is a April 2022 and I am the first owner apart fro Bristol Camper Company and it has been with them since new and only had 350 delivery miles on the clock so I can't see it is anything to do with age !
Alan Spencer
Member
Obviously not after reading Pete C's reply !
BINGO !!! I have just looked at my tracker display and it said that my battery is on 14.4 !!! So I have been out and looked at the charger and it is now in"Care" mode ! Relief ! Have Tea Break Guys !
BINGO !!! I have just looked at my tracker display and it said that my battery is on 14.4 !!! So I have been out and looked at the charger and it is now in"Care" mode ! Relief ! Have Tea Break Guys !
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