Electical fault? dead battery?

[GICarey]

hi Folks,

Well, after my head gasket failure was resolved (replacement engine from discount trucks got be going again; they appear to be great in the pre-sales & the doing; less great in post-sales communication...), I fitted a leisure battery and split-charge relay kit (willinton via ebay shop), and off we went for a lovely couple of weeks away using the bongo for what it was bought for

Used the car, mostly at weekends on and off since then. She's not been turned over, however, for about a fortnight now, just sat on the driveway all big & green.

However, the dog and I went out to the Bongo today, planning on a couple mile run out into the countryside then an afternoons walking.

However, el-Bongo, she was dead. Appears to have run out of electricity. We took the misses corsa (always fun with an 8st great dane/german shep. cross in the back!).

Upon return, grabbed my multi-meter, and checked both batteries. Both returning about 1.8v checked inside, nothing obvious left on (and, to be honest, most things: lights, cig-socket, blinds, inverter, stereo all run solely off the leisure battery now anyway), headlight switch not on, etc, though am willing to accept it's a possible reason for dead battery.

OK - lets try charging thinks I, and retrieves the device from the garage.

Connected to main battery, with all wiring in situ. Plug in, pop - fuse blown puzzled, I wonder if there's some heavy drain on the battery, possibly a wiring fault? possibly something with the split charge relay, so to be safe completely disconnect the battery from the car, connect up the charger, replace the fuse, plug in - pop- fuse blown again

Odd thinks I, wonder if the charger has gone bad? Connect it to LB, new fuse, plug in, all good, happily forcing in just shy of 14v, interior lighting starts to work when doors open, etc.


Soo - my question then, is where do I start? Is there an obvious battery fault which is the cause of the fuse blowing? I can probably jump start the Bongo from the corsa tomorrow (poor corsa!) and see if it can put any juice back into the battery itself, but wondered, if there is a battery fault, is that likely to be a bad thing to do? dangerous?

Or, could it be a wiring fault that's caused all this? and its just that the voltage is so low that it's popping the fuse? If so, any tips on where to start tracking this down? could the voltage sensing relay in the split wiring kit have gone bad? any way to test this with a multimeter? etc?


Thanks, as always, for your advice and help!

Gavin.

[g8dhe]

OK several things, first as both batteries are discharged, then are you sure that the alternator is charging ? Normally only one battery would be flat unless neither was being charged.

As to the problem with the fuse blowing, which fuse is this ? It sounds like the fuse on the charger itself, what is it rated at and what is the charger rated at supplying at maximum ? Given that it is charging the L/B but blowing on the S/B then provided the battery is disconnected from the car then it does sound like a battery fault. Normally the battery volts will rise rapidly (a few seconds is enough) to about 12v after a complete discharge, if it isn't then it might well have shorted out internally. In which case its a new battery. However if the charger is just a little float charger with a max charge rate of about 4A then it might well blow a fuse trying to charge a very, very flat battery. If that should be the case try using an old headlight bulb to connect the charged L/B to the flat S/B , outside the car, this will ensure that neither battery can be damaged whilst getting a bit of charge into the S/B - Connect -ve of batteries together then connect the headlight between the two +ve terminals, the light will glow to start with but within a few minutes should start to dim, at which point you can revert to normal charging from the charger, if the headlight doesn't dim after a few minutes then the S/B battery is almost certainly dead.

[GICarey]

OK several things, first as both batteries are discharged, then are you sure that the alternator is charging ?

Nope, not certain, haven't had Bongo running today to test, and hadn't noticed an issue since last parking it up (last drive was middle of the night, and no noticable issue with lights, etc, at the time though).

As to the problem with the fuse blowing, which fuse is this ? It sounds like the fuse on the charger itself, what is it rated at and what is the charger rated at supplying at maximum ?

Correct, it's a Halfords charger, one of these, with 2 switches (standard/sealed battery type and bike/other), with a 20amp blade fuse in it. Does charge/maintain, and claims not to charge anything below 6 volts, though it appears to be kicking 14v into the LB at the moment...

If that should be the case try using an old headlight bulb to connect the charged L/B to the flat S/B , outside the car, this will ensure that neither battery can be damaged whilst getting a bit of charge into the S/B - Connect -ve of batteries together then connect the headlight between the two +ve terminals, the light will glow to start with but within a few minutes should start to dim, at which point you can revert to normal charging from the charger, if the headlight doesn't dim after a few minutes then the S/B battery is almost certainly dead.

OK, thanks, provided the LB is showing reasonable voltage in the morning, I'll dig out the requisite parts and give this a go tomorrow. Presume this is a better method than firing up the corsa and connecting the Bongo battery (out of the bongo) to the corsa via jump leads?

Thanks,

Gav.

[g8dhe]

It will be a bit gentler than slapping an alternator across a totally flat battery, it also saves the alternator fuse in the Corsa should you have a faulty battery!

[GICarey]

OK, great, I shall make up the necessary wiring tomorrow & report back

Thanks,

Gav.

[TWO BLUE]

Mmmm!!! Interesting!! Had same problem after being parked up a week. I charged leisure battery with charger that sounds identical to one that GICarey used and subsequently found blown fuse on split wiring. Once replaced all seems to be charged again. Though I have invested in two solar chargers, one for main and one for leisure battery.
I may still have a problem though so will be interested to read update on this.

[GICarey]

Can confirm no blown fuses anywhere on the Bongo / split wiring harness at this point.

[GICarey]

Reporting in!

OK, so, after a night of charging, the leisure battery was back to ~13v after being taken off charge and allowed to rest. Starter Battery was showing 5v now after a night of rest, disconnected from the rest of the Bongo (up from 1.8v which both batteries were showing when everything was connected, and up from 4ish volts which the SB was showing when first disconnected yesterday. I'm going to assume temp and movement making most of the difference. Curiosity made me risk another fuse in the charger at this level. it blew.

Took both batteries out of the Bongo and into the garage, grabbed spare headlight bulb, made up the necessary wiring to connect headlight bulb across two +ve terminals and a simple lead between two -ve terminals, connected it all up.

Bulb lit, dimly (much more dimly than if connected straight across the LB, orange light rather than yellow, like a torch when your batteries are on your way out), and after about 2 mins was almost out.

Disconnected wiring and checked voltages across both batteries. LB showing 12.4v now, SB showing 6.8v

Tentatively connected the Halfords charger, set switches for standard battery, and plugged it in. The fuse didn't blow and the battery appears to be charging (it's making gurgling noises in there, I presume that's normal?), and the voltage across the battery, whilst charging, is showing at around 12.5v (down from the 13v+ shown when the LB was charging, guess this may be the difference between sealed and standard settings on the charger?).

Crossing fingers now then, will pop to check on it later and report back in when it's all back in the Bongo, after which I'll keep an eye on voltages with the multimeter over the next few days, to see if there is any drop which would suggest drain on the system somewhere.

Gav.

[GICarey]

Old physics lectures just came back to me, and I now understand the reason for the dimness of the bulb.

13v - 5v = 8v therefore bulb lighting as if connected to a battery with 8v of charge.

As power travels between batteries, 13v became 12.5v and 5v became 6.8v

12.5v - 6.8v = 5.7v therefore bulb now lighting as if connected to a battery with 5.7v of charge, not really enough to give it any oomph!

Magic, v good Mr g8dhe.

Regards,

Gavin.

[GICarey]

Curious.

After an hour (much shorter than I'd expected from a 7.5A max charger) the charger slipped into "Maintaining" mode, removing charger and testing with multi-meter showed a voltage in the battery of 12.5v.

Popped the charger onto the LB to get that up-to-full again and let the SB rest.

An hour later, again, the SB voltage had dropped down to about 11.5v, putting the headlamp bulb accross it, it drops to 10.5ish volts with a fairly bright (to my eyes in my dark garage) shining bulb, appears to be holding voltage / slowly creeping upwards again.

Still, odd that it'd dropped from 12.5v to 11.5v in an hour, so it's now back on the charger again. Just for fun I connected the aforementioned bulb in series with the battery so it went charger +ve -> battery +ve, battery -ve to wire to bulb, bulb to charger -ve. This gave an extremly dim glowing bulb and an around 12.5v voltage at the battery. Not really sure what I was trying to prove, I took this all off again and have left the SB battery, once again, charging.

G.

[mikeonb4c]

I'm suspicious of the condition of the battery(s). They could do witha proper load test after charging to ascertain their condition. Is much known about their age / pedigree? And they may (esp the SB) have been damaged by being heavily discharged. If the starter battery fails the load test (g8dhe might advise on how do do one if he hasn't already in this thread -sorry as I've only skimmed through it) then clearly a new one has to be bought. But as it uncertain yet what might have caused it then I'd isolate it from the willinton / LB setup until / unless I was confident it wasn't involved in cuasing a current drain (I assume the willinton VSR was set up as per instructions so that isolated the LB when engine is off?).

Sorry if this is a load of tosh - I'm always inclined towards non-techy workarounds while I investigate potential source probs at a snails pace.

Great news about you being back on the road though - hopefully we'll get the Bongo settled down and doing what it was bought to do

[GICarey]

Hey Mike,

I'm suspicious of the condition of the battery(s

Yes, me too, showing "charged" that quickly, from a known dead state points, to me, to dodgy battery.

The LB is pretty much brand new, and appeared to be fine during our camping trip (provided us with uninterrupted lighting, music, charged mobiles and charged laptops throughout a fortnight away in August, with the engine being run every day or every other day), so, if either of the pair are dodgy, I suspect it's the SB rather than the LB, though the question remains, did the dodgy SB drag the LB flat also, or is there "something else" afoot, wiring wise, which I've yet to discover.

A quick resistance test across the willinton VSR wiring shows no current passing when it's not connected to either battery, will need to see if it's triggering, however, when everything is back in place and charged, but, for the starter battery at least, I suspect this won't be until I've proven it's good or otherwise.

For a "load test" am considering putting the electric coolbox across it in the garage to see how well, or otherwise, it fares. Other recommendations appreciated, ofcourse.

Regards,

Gavin.

[mikeonb4c]

Good luck with it Gavin - I'm sure it'll get sorted OK but possibly with purchase of a new SB being on the cards (pay the extra and go for a good Ah one - say 95Ah or even 105Ah - as I've a strong hunch it is worth it in terms of ensuring glowplugs maintain a good glow when cranking because battery is not being pushed hard, which also lengthens battery life)

[g8dhe]

Curious.

After an hour (much shorter than I'd expected from a 7.5A max charger) the charger slipped into "Maintaining" mode, removing charger and testing with multi-meter showed a voltage in the battery of 12.5v.

Popped the charger onto the LB to get that up-to-full again and let the SB rest.

An hour later, again, the SB voltage had dropped down to about 11.5v, putting the headlamp bulb accross it, it drops to 10.5ish volts with a fairly bright (to my eyes in my dark garage) shining bulb, appears to be holding voltage / slowly creeping upwards again.

Still, odd that it'd dropped from 12.5v to 11.5v in an hour, so it's now back on the charger again. Just for fun I connected the aforementioned bulb in series with the battery so it went charger +ve -> battery +ve, battery -ve to wire to bulb, bulb to charger -ve. This gave an extremly dim glowing bulb and an around 12.5v voltage at the battery. Not really sure what I was trying to prove, I took this all off again and have left the SB battery, once again, charging.

G.

OK that's about what I would expect, the voltage will rise rapidly, now you need to give the starter battery a good solid charge for 24 hours minimum, after that you can try loading it again. If the voltage drops by more than 0.8-1.0 volts then the battery is on its way out most definitely, but until you have put a good charge into it in the chargers "mtce" mode then the battery will always be on the low side. I would expect the charger in "Mtce" mode to be putting in between 1-3 Amps so it needs at least 36-48 hours to be fully charged.

But do remember that re-charging the battery is one thing - but what caused them both to flatten in the first place ? Until you solve that then the problem is only going to persist. you need to measure the current drawn from each battery when everything is turned "Off" and see what is going on.

[GICarey]

I would expect the charger in "Mtce" mode to be putting in between 1-3 Amps so it needs at least 36-48 hours to be fully charged.

Ah, OK, i'll pop out and put it back on charge again and leave till i get home from work on Tuesday night.

ut do remember that re-charging the battery is one thing - but what caused them both to flatten in the first place ? Until you solve that then the problem is only going to persist. you need to measure the current drawn from each battery when everything is turned "Off" and see what is going on.

Quite right, I shall rebuild in stages. It's soon to be too cold to go camping anyway, so for the time being, the LB side, including split-charge kit, can stay disconnected for the time being (replacing 3 spade terminals with fuses will put the stereo, cig sockets, blinds and lights back on the SB side, and my other additions aren't needed when not camping), which gives me just the "standard" wiring to contend with. I shall experiment with the multi-meter to see how the Amp sensing side of it works

Gav.