Battery fault? and need a new charger maybe
Discussion
As everything seems to go wrong at once I think I need a new battery charger. Story is I thought my van battery might be on the way out (starting slightly slower in the mornings and economy mode showing on the dash within minutes of the ignition coming on, also stop start never activated either.) the vans only 5 year old but I decided to get a new battery for it, put it on and for a couple of weeks it started fine and even the stop start started working again.
Fast forward to yesterday and I went out to the van and the battery was completely dead, put the old one back on (which was showing 12.5V) and it started, left an ammeter in series with the battery and no obvious current drain or anything although the meter was jumping around a bit from a couple of amps to 0 until it all went to sleep.
What I have discovered though is the interior light was misbehaving, don't ask me how but inside with the doors shut one of the two lights was flashing on and off at regular intervals which would coincide with meter jumping about, on the other light the switch was half way between two positions and switching this off stopped the other light from flashing. So I reckon for now somehow that was draining the battery maybe. Its started fine this morning anyway with the old battery one so I'll have to see how it goes.
This brings me onto my next point about the charger, I tried charging the brand new battery but it won't go above 11.8 volts but also testing across the charger leads that's also showing 11.8 volts open circuit. It is old though, probably as old as me, it used to be my dads and must be from the 70's, its also only a 4A one, its also worked in the past though.
Annoyingly the van's engine light is now on as well since the battery went flat and as per my other thread my laptop is currently broken so I cant even see what's going on. So instead of it being a simple case of leaving the lights on or something I've had to contend with flat batteries, disco lights, iffy chargers, iffy batteries and broken laptops, oh yea, the multi meter broke as well so I had to take that to bits to repair it before I could diagnose anything. But I think I need to start with a new charger, the battery is an EFB one for the stop start so would something like this be ok.
https://www.amazon.co.uk/Automatic-Temperature-Com...
Fast forward to yesterday and I went out to the van and the battery was completely dead, put the old one back on (which was showing 12.5V) and it started, left an ammeter in series with the battery and no obvious current drain or anything although the meter was jumping around a bit from a couple of amps to 0 until it all went to sleep.
What I have discovered though is the interior light was misbehaving, don't ask me how but inside with the doors shut one of the two lights was flashing on and off at regular intervals which would coincide with meter jumping about, on the other light the switch was half way between two positions and switching this off stopped the other light from flashing. So I reckon for now somehow that was draining the battery maybe. Its started fine this morning anyway with the old battery one so I'll have to see how it goes.
This brings me onto my next point about the charger, I tried charging the brand new battery but it won't go above 11.8 volts but also testing across the charger leads that's also showing 11.8 volts open circuit. It is old though, probably as old as me, it used to be my dads and must be from the 70's, its also only a 4A one, its also worked in the past though.
Annoyingly the van's engine light is now on as well since the battery went flat and as per my other thread my laptop is currently broken so I cant even see what's going on. So instead of it being a simple case of leaving the lights on or something I've had to contend with flat batteries, disco lights, iffy chargers, iffy batteries and broken laptops, oh yea, the multi meter broke as well so I had to take that to bits to repair it before I could diagnose anything. But I think I need to start with a new charger, the battery is an EFB one for the stop start so would something like this be ok.
https://www.amazon.co.uk/Automatic-Temperature-Com...
Edited by Frane Selak on Friday 13th February 16:41
Sorry to hear of your multiple woes adding to each other.
My starting point with what you are having would be you need a fully charged battery to start with, so if your charger will not give out more that 11.8v then it needs to go.
So, does it go above 11.8 when connected to the 12.5v battery?
If so connect both together + to +, - to - and see what happens, then disconnect the 12.5v battery and see what happens.
I say this as the charger may think that 11.8 is too dead to try to charge.
Then see if you can completely turn off the interior lights or remove the fuse etc to see if that is what is draining the battery.
My starting point with what you are having would be you need a fully charged battery to start with, so if your charger will not give out more that 11.8v then it needs to go.
So, does it go above 11.8 when connected to the 12.5v battery?
If so connect both together + to +, - to - and see what happens, then disconnect the 12.5v battery and see what happens.
I say this as the charger may think that 11.8 is too dead to try to charge.
Then see if you can completely turn off the interior lights or remove the fuse etc to see if that is what is draining the battery.
Its certainly strange, I got a cheapo charger off amazon so gave it a try this morning, put it on for 2 minutes and it was saying the battery was 80% charged. So tried the original old one. It now reads 14/15V without any load on it which it wasn't doing yesterday although it was quite warm when I checked it.
with it connected to the battery its now showing 12 volts. (This is after the new charger had been on for 2 minutes, it was previously showing 11.8)
That charger is supposedly a smart charger with different modes for different types of batteries, its currently set on EFB/AGM but the mode button doesn't do anything, a couple of people in the comments mentioned this as well, I'm guessing it hasn't actually got different modes and its just a couple of LED's driven off the power supply to make it look like it is special, but it was only £20. One for Big Clive to look at.
The new charger connected to the battery shows 13.7 volts.
with it connected to the battery its now showing 12 volts. (This is after the new charger had been on for 2 minutes, it was previously showing 11.8)
That charger is supposedly a smart charger with different modes for different types of batteries, its currently set on EFB/AGM but the mode button doesn't do anything, a couple of people in the comments mentioned this as well, I'm guessing it hasn't actually got different modes and its just a couple of LED's driven off the power supply to make it look like it is special, but it was only £20. One for Big Clive to look at.
The new charger connected to the battery shows 13.7 volts.
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