Hi, I'm at a loss, I've had a new starter and leisure battery installed in the past year and have a B2B Victron Smart Charger, which should be set-up correctly, but I've left my van for a week to find that the starter battery is down to 5 volts. Does anyone have any recommendations as to what I can do, please?
Starter battery draining and dead after a few days [Resolved]
- Thread starter KenA
- Start date
If the battery is flat then there is a cause and you need to find it
Initially there are three possibilities
You have a faulty battery
You have a faulty charging system
You have a parasitic drain on the battery
A little more background would be good
Do you have tools like a multi meter etc ?
Initially there are three possibilities
You have a faulty battery
You have a faulty charging system
You have a parasitic drain on the battery
A little more background would be good
Do you have tools like a multi meter etc ?
If i were in your situation i think i would be attaching a BM2 battery monitor to the engine battery to log and monitor voltages
1 Charge the battery so you can start the van then check the battery voltage at rest and when the vehicle is running and confirm the alternator is putting out a good charging voltage, this will prove the vehicle is capable of keeping the battery charged when being used
2 With a fully charged battery go to your local battery shop and get the battery load tested, this will prove the battery is not faulty and is capable of holding of a decent charge
Then you are down to checking any parasitic drains on the battery when it is parked up
3 The easiest way to check for parasitic drains is to use a clamp meter on the battery cables when the vehicle is turned off and not being used but its not your average tool that people have so you may need to try a few trial and error bits !
The obvious starting point here is your leisure battery setup, in fact anything connected to vehicle that is not factory fitted
1 Charge the battery so you can start the van then check the battery voltage at rest and when the vehicle is running and confirm the alternator is putting out a good charging voltage, this will prove the vehicle is capable of keeping the battery charged when being used
2 With a fully charged battery go to your local battery shop and get the battery load tested, this will prove the battery is not faulty and is capable of holding of a decent charge
Then you are down to checking any parasitic drains on the battery when it is parked up
3 The easiest way to check for parasitic drains is to use a clamp meter on the battery cables when the vehicle is turned off and not being used but its not your average tool that people have so you may need to try a few trial and error bits !
The obvious starting point here is your leisure battery setup, in fact anything connected to vehicle that is not factory fitted
Thanks for the replies. The draining battery issue has been going on for a couple of years, at first, I thought it was the VSR that I had put on by the chap who converted my van, so I replaced it with a Victron B2B smart charger. I also had a new battery put in. The issue still arose, and from memory, I had the B2B charger set up as a power supply and not as a charger, so changed it.
The charger then broke, so I had it replaced, but even whilst the old charger was faulty, the starter battery would drain, but I was using the vehicle enough that it didn't completely discharge. I've been away for a week to find my battery completely dead and registering 5 volts. A jump start or using one of these: https://www.amazon.co.uk/Maypole-7423A-Battery-Charger-Electronic/dp/B009A83P1E/ref=sr_1_32?crid=JWU5Q27K31JE&keywords=smart+battery+charger+car&qid=1652124009&sprefix=smart+battery+charger+car,aps,107&sr=8-32 hasn't helped in the slightest.
The charger then broke, so I had it replaced, but even whilst the old charger was faulty, the starter battery would drain, but I was using the vehicle enough that it didn't completely discharge. I've been away for a week to find my battery completely dead and registering 5 volts. A jump start or using one of these: https://www.amazon.co.uk/Maypole-7423A-Battery-Charger-Electronic/dp/B009A83P1E/ref=sr_1_32?crid=JWU5Q27K31JE&keywords=smart+battery+charger+car&qid=1652124009&sprefix=smart+battery+charger+car,aps,107&sr=8-32 hasn't helped in the slightest.
You'll already know this but the starter battery shouldn't be draining after 1 week.
I agree with @Pauly.
Go back to basics by removing any additional connections to the starter battery. You mention a B2B charger. Remove all connections at the starter battery + term other than the OEM connections (which includes your B2B charger).
Did you ever resolove your stop/start issues?
I agree with @Pauly.
Go back to basics by removing any additional connections to the starter battery. You mention a B2B charger. Remove all connections at the starter battery + term other than the OEM connections (which includes your B2B charger).
Did you ever resolove your stop/start issues?
Hi, thanks for that and nope, I've not had any luck with the stop/start issues, annoyingly.
I've attached a BM2 monitor to the battery and fully charged it from the mains yesterday evening. It was at 98% at about 8pm and dropped to about 50% within a couple of hours.
I had thought that, too. Annoying, as the battery was only installed last October.
Given that, it's likely some underlying issue (likely some unwanted high drain) has killed the battery so I would focus on discovering what that underlying issue is before installing a new battery - otherwise you run the risk of sticking a new battery in only to have it damaged again. If you do stick a new battery in, check your BM2 daily to hopefully spot an issue before any real damage occurs.
First thing to probably check is the Victron DC-DC and whether that's correctly installed/configured to only draw current when the engine is running.
No evidence of significant drain there, doesn't rule it out completely though - just that it's likely not happening right now. Maybe start the van up and check that the voltage goes high from the alternator. Also check victron DC-DC status before/after engine starting to check nothing odd there.
Also, can we see a picture of your starter? Worth checking nothing is wired up in such a way that it's bypassing the VW shunt that monitors the starter state of charge - should be nothing on the negative terminal other than the single factory connection.
The Victron DC-DC was off before I started the van, then went to absorbtion charge, before turning back off.
Both the alternator and the Victron DC-DC seem to be behaving as expected from that brief test, and nothing problematic that I can see on the negative terminal.
Is it possible the current starter got hammered from one known event rather than an ongoing issue?
What mains charger did you use to charge the starter? Worth making sure it really is dead before shelling out for a new one I suppose.
Is it possible the current starter got hammered from one known event rather than an ongoing issue?
What mains charger did you use to charge the starter? Worth making sure it really is dead before shelling out for a new one I suppose.
I've use a Maypole 7423A Battery Charger.
Could it be as simple as the battery wasn't coded properly (and now it's probably shot)? The chap that fitted it wasn't the sharpest tool in the box, he first installed an EFB battery and then when I brought this up with him, he replied that he just ordered the battery that the computer told him to when he entered my registration.
That said, the same thing did happen to my old AGM battery. That was after 2 weeks of sitting on a driveway, late autumn, but even that doesn't seem like too long.
Could it be as simple as the battery wasn't coded properly (and now it's probably shot)? The chap that fitted it wasn't the sharpest tool in the box, he first installed an EFB battery and then when I brought this up with him, he replied that he just ordered the battery that the computer told him to when he entered my registration.
That said, the same thing did happen to my old AGM battery. That was after 2 weeks of sitting on a driveway, late autumn, but even that doesn't seem like too long.
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Hi. Does your Victron dc-dc have an IGN+ or an ‘engine running’ connection to the fuseboard or BCM? I’m only familiar with Renogy dc-dc. The theory being if that’s not connected and/or the auto-sensing isn’t working for some reason, the dc-dc might bulk charge the leisure battery whilst the alternator isn’t running, depleting the starter.
(Just realised @t0mb0 suggested the same above).
(Just realised @t0mb0 suggested the same above).
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