Flat Vehicle battery [Resolved]

[Glennpea123]

Transporter T6
Hi all, my battery has gone flat again. It was new a few weeks ago because old one was old and kept going flat, now this new one has.
Put on charge this morning and alarm came on and i couldn't turn it off..eventually stopped. Am i doing something wrong with how I leave the PMS selectors?
Please see photo of how i leave it, although have now put battery selector to OFF position, I have been leaving it on VAN...is this wrong or should it not matter?
The only other thing is I have had a cycle carrier and electrics have been left connected, surely this shouldn't matter? Haven't started van for about 1 week.
Any help would be greatly appreciated as this is baffling me.



Also, think I was told this before......I'm assuming the tails on Starter battery negative terminal which my conversion man fitted, as in photo, should not be there and down to earth somewhere. Could leisure battery be pulling starter battery down through these tails or the split charge relay be faulty? excuse my ignorance as I'm not good with electrics.
Ta in advance for help and ideas.

 

[roadtripper]

Those negative tails should certainly be on a chassis ground - the one just to the right of the battery on the wing is handy.

At the minute they are bypassing the current shunt so all the energy flowing through that circuit isn't seen by the main ECU so it won't bother putting it back - leading to a poorly charging battery.

 

[roadtripper]

The PMS dates from Caravan days so here "CAR" means starter battery and "CaraVAN" means leisure battery.

Leaving the battery selector OFF if you are parked up and not using the van is good, but it shouldn't matter too much if left on VAN.

The big question is how is your leisure battery being charged from the van electrics?

And just to be clear which battery are you having trouble with, starter or leisure?

 

[Glennpea123]

Those negative tails should certainly be on a chassis ground - the one just to the right of the battery on the wing is handy.

At the minute they are bypassing the current shunt so all the energy flowing through that circuit isn't seen by the main ECU so it won't bother putting it back - leading to a poorly charging battery.

Thankyou for reply, so them tails on the neg terminal are to do with the split charge relay system?

The PMS dates from Caravan days so here "CAR" means starter battery and "CaraVAN" means leisure battery.

Leaving the battery selector OFF if you are parked up and not using the van is good, but it shouldn't matter too much if left on VAN.

The big question is how is your leisure battery being charged from the van electrics?

And just to be clear which battery are you having trouble with, starter or leisure?

Sorry its the starter battery, and it's new. All dash lights were out so completely dead, now charging and now have flickering lights on dash.

Starter battery bottom pic.....so are those tails something to do with returning from neg terminal on leisure battery, and if so, by moving them to chassis earth that will then will sort the problem? I can't tell exactly where the white tails are going but seems to be to the relay ( little black box left of neg terminal), could this be faulty?

 

[roadtripper]

I'm not sure what they are but they are not standard and all negative current needs to flow through the shunt on the terminal so all negative/ground lines need to be to a chassis ground not the battery terminal.

The shunt is used for the ECU to monitor every fraction of charge in and out so it can very accurately know the state of the battery. It might not completely explain a flat battery but it's not going to help as the van will think there is considerable more charge in the battery than there is.

How is your leisure battery being charged? Can you post some pictures?

 

[Glennpea123]

Leisure battery seems to be charged from pos terminal then through fuses to relay then to leisure battery etc, it all looks ok but difficult to trace wiring as all taped up with other wiring. Have sent couple of pics, appreciate your help thank you

 

[Dellmassive]

Those white cables are part of some towing electrics, as are the blade fuses in front of the battery.

As above, they need to be moved over to the light bracket bolt.

 

[roadtripper]

I think our posts crossed...

Couple of key questions:
1. Is your van a stop start system?
2. Has it been fitted with an aftermarket towbar?

Reasons for questions:
1. Your main starter battery is an AGM so likely stop start, but your leisure battery looks like a standard leisure battery - that's not a good combination to be using a split charge relay, that should be using a DC-DC charger system.
2. There is a large white module marked Right Connections - and they seem to do towbar electrics. You mentioned you leave a trailer board in.

I think what you have is not one smoking gun but a series of issues that are impacting you:
a. You have load bypassing the charge monitoring - either the leisure charging, the towbar electrics or both. This will be causing the van to under charge the starter battery.
b. You have miss matched battery types with what looks like a split charge relay and not a DC-DC charger, that's going to be impacting the charging and health of both batteries long term.
c. Leaving the towbar electrics connected - minor but may be a parasitic load bypassing the monitoring.

First thing I would do is move those negative feeds across to the bolt on the wing (pointed out by multimeter probe here) as that might improve things enough for the interim.

 

[Glennpea123]

I'm not sure what they are but they are not standard and all negative current needs to flow through the shunt on the terminal so all negative/ground lines need to be to a chassis ground not the battery terminal.

The shunt is used for the ECU to monitor every fraction of charge in and out so it can very accurately know the state of the battery. It might not completely explain a flat battery but it's not going to help as the van will think there is considerable more charge in the battery than there is.

How is your leisure battery being charged? Can you post some pictures?

Have posted pics of leisure and starter batteries.
Leisure battery seems to be charged from pos terminal of starter battery, then through fuses to relay,,,difficult to trace wiring as taped up to other wiring.

 

[roadtripper]

As an aside I'm not convinced that the relay by the battery is anything to do with the leisure charging as it's also branded Right Connections so more likely towing electrics - possibly a relay for the switched fridge feed in the towing socket.

Have a dig around the leisure battery location and under the seats - somewhere there is either a split charging relay (not great) or a DC-DC charger (much better)

 

[Glennpea123]

I think our posts crossed...

Couple of key questions:
1. Is your van a stop start system?
2. Has it been fitted with an aftermarket towbar?

Reasons for questions:
1. Your main starter battery is an AGM so likely stop start, but your leisure battery looks like a standard leisure battery - that's not a good combination to be using a split charge relay, that should be using a DC-DC charger system.
2. There is a large white module marked Right Connections - and they seem to do towbar electrics. You mentioned you leave a trailer board in.

I think what you have is not one smoking gun but a series of issues that are impacting you:
a. You have load bypassing the charge monitoring - either the leisure charging, the towbar electrics or both. This will be causing the van to under charge the starter battery.
b. You have miss matched battery types with what looks like a split charge relay and not a DC-DC charger, that's going to be impacting the charging and health of both batteries long term.
c. Leaving the towbar electrics connected - minor but may be a parasitic load bypassing the monitoring.

First thing I would do is move those negative feeds across to the bolt on the wing (pointed out by multimeter probe here) as that might improve things enough for the interim.

View attachment 211304

You are making things a lot clearer to me and i really appreciate your time. Yes starter battery stop/start. Yes a tow bar has been fitted and it is the proper one (so we were told), cost nearly £700, and that module is the tower electrics. Because I'm useless at electrics lol, I'm a bit hesitant to move the said tails, but I will put them where you pointed out. Is it ok to move them while battery is charging or safer off charge? may have to lengthen cables as well.

Those white cables are part of some towing electrics, as are the blade fuses in front of the battery.

As above, they need to be moved over to the light bracket bolt.

Thank you much appreciated

 

[Glennpea123]

As an aside I'm not convinced that the relay by the battery is anything to do with the leisure charging as it's also branded Right Connections so more likely towing electrics - possibly a relay for the switched fridge feed in the towing socket.

Have a dig around the leisure battery location and under the seats - somewhere there is either a split charging relay (not great) or a DC-DC charger (much better)

This was lurking under the seat, fuses and whatever the other is?....I'm learning more every minute lol.

 

[roadtripper]

If you are not confident then consider finding an auto electrician or seeing if someone on the forum is near to you and may help for some beer tokens. Make a plan, get the parts and make sure you're happy before diving in with the spanners.

If you do move them then do so with the electrics as dormant as possible.

One thing you must take care not to do is to disconnect the negative terminal from the battery, this can disrupt electronics. I've not done enough with my van to know the best way to do this but @Dellmassive likely has some advice in his extensive threads, have a search.

Moving grounds is relatively safe as they can't short against the body, just take care not to short against anything live.

 

[roadtripper]

This was lurking under the seat....I'm learning more every minute lol.

View attachment 211321

Not a charger though, that's a secondary fuse box, but keep tracing and try and draw up a circuit diagram

Making sure you know what's there to start with before making changes is a good thing.

As a partial solution while you make a plan you could get a 5A maintenance smart charger from NoCo or CTEK and keep your main battery charged. Both systems you can get an adaptor to plug into a cigarette socket and the one by the gear selector is usually connected to the starter battery - would save you popping the bonnet all the time.

 

[Glennpea123]

Not a charger though, that's a secondary fuse box, but keep tracing and try and draw up a circuit diagram

Making sure you know what's there to start with before making changes is a good thing.

As a partial solution while you make a plan you could get a 5A maintenance smart charger from NoCo or CTEK and keep your main battery charged. Both systems you can get an adaptor to plug into a cigarette socket and the one by the gear selector is usually connected to the starter battery - would save you popping the bonnet all the time.

Thanks for all your help...will let you know the outcome

 

[Glennpea123]

Thanks for all your help...will let you know the outcome

Looks like it's a DC to DC charger or a smart relay?

 

[Higgidav]

Looks like an Ablemail 12-12-30 DC-DC.

 

[roadtripper]

That looks hopeful, try and find out what it is and how it's triggered.

A potential issue could be the DC-DC charger staying in and slowly draining the starter.

 

[Higgidav]

Download the Ablemail instructions and the small light in the second picture will tell you the status. I think I can also see the sense wire (small wire under the white cap in the photo) which will either be connected to the stater battery positive or ignition feed.

If everything is working properly it would be worth considering adding an Ablemail AMT12-2 trickle charger to maintain the starter battery. There are lots of posts about this on the forum.

 

[Glennpea123]

Download the Ablemail instructions and the small light in the second picture will tell you the status. I think I can also see the sense wire (small wire under the white cap in the photo) which will either be connected to the stater battery positive or ignition feed.

If everything is working properly it would be worth considering adding an Ablemail AMT12-2 trickle charger to maintain the starter battery. There are lots of posts about this on the forum.

Red light (if it isAblemail) says 'fast charging' should go green when charged enough, will keep on charge overnight and see if light goes green. thank you