New Leisure Battery - New issue! :(

Wisewoman

Full Member
Posts
546
Likes
593
Hi all,

So some of you have been a really big help with troubleshooting my leisure battery and gave me a lovely warm fuzzy feeling of being helped! Many thanks.

I have now just put the new leisure battery in (fully charged) and my one year old starter batter (also fully charged) into the van - hey presto - the van bursts back into life and all appeared well until...

After about 30 seconds with engine on and idling , the battery light on my dash starts to faintly illuminate! The minute i hit the acceleration pedal - it goes away again. This faint illumination of battery light didn't happen before I changed the batteries - so whats the most likely explanation?

Do I need to check the wiring from alternator to battery incase I've pulled it a bit more than I should have or disturbed it in some other way?

I'm hoping that someone out there can just go - 'Oh you've probably just..... blah blah'

Thanks,
Melissa
 
The time to worry is when it comes on while you're driving. Could be tick over is a little low or it's just the Fiat Gremlins at work. Mine lights up like a Christmas Tree if I turn the Cruise Control on, I get all sorts of dim warning lights. Mine is a problem with the dash but I can live with it till I get somewhere near Portsmouth to get it fixed.
 
Hi all,

So some of you have been a really big help with troubleshooting my leisure battery and gave me a lovely warm fuzzy feeling of being helped! Many thanks.

I have now just put the new leisure battery in (fully charged) and my one year old starter batter (also fully charged) into the van - hey presto - the van bursts back into life and all appeared well until...

After about 30 seconds with engine on and idling , the battery light on my dash starts to faintly illuminate! The minute i hit the acceleration pedal - it goes away again. This faint illumination of battery light didn't happen before I changed the batteries - so whats the most likely explanation?

Do I need to check the wiring from alternator to battery incase I've pulled it a bit more than I should have or disturbed it in some other way?

I'm hoping that someone out there can just go - 'Oh you've probably just..... blah blah'

Thanks,
Melissa

Well it could be you have disturbed a poor connection, but have you now got a way of monitoring the starter and leisure batteries voltages ?
If you could monitor the starter battery voltage while the engine is running then you will be able to see if you have anything to be concerned about. for instance my car battery with the engine running is at about 14.4 volts. :)
 
I believe the light is driven by any difference between what the vehicle battery produces and what the alternator produces. If everything is connected properly (I.e. No loose wires) then maybe the alternator is struggling. I didn’t read an earlier thread but if the old battery died because of not being charged properly (alternator not making enough volts) putting a nice new battery in might make the light glow. Just my theory! Do you know the alternator is good?

strictly amateur motor electrician speaking
 
Hi all,

Great solid advice to check the earths on both batteries - Thanks - I will have a fiddle with them tomorrow morning when its light again.

Harrow - Please dont put thoughts of poor connection in my head- things like that just seem impossible to resolve. I also did put my old multimeter on the batteries with engine running and idling - main battery 14.45 and leisure at 14.05V. The flickering faint red light would have been on at this point!

:)
 
I believe the light is driven by any difference between what the vehicle battery produces and what the alternator produces. If everything is connected properly (I.e. No loose wires) then maybe the alternator is struggling. I didn’t read an earlier thread but if the old battery died because of not being charged properly (alternator not making enough volts) putting a nice new battery in might make the light glow. Just my theory! Do you know the alternator is good?

strictly amateur motor electrician speaking
Thanks for your reply - I'm pretty sure the alternator should be fine - its never illuminated in a strange way before.

My leisure battery had given up the ghost which led to me having both batteries out the van - the tale can be read here :)
 
Hi all,

Great solid advice to check the earths on both batteries - Thanks - I will have a fiddle with them tomorrow morning when its light again.

Harrow - Please dont put thoughts of poor connection in my head- things like that just seem impossible to resolve. I also did put my old multimeter on the batteries with engine running and idling - main battery 14.45 and leisure at 14.05V. The flickering faint red light would have been on at this point!

:)
If you can get those voltages then the output of the alternator is looking good :)
 
Do check the battery terminals and the connecting clamps, it's always a good idea to give them a wire brushing then smear with vaseline when putting back together. The lead posts do oxidise naturally and the brass clamps corrode if there is any slight acid contamination, if they are sealed together with petroleum jelly this is much less of an issue and is the recommended practice. You can buy special terminal grease in small tubes but I'm not sure it's much different.

It used to be that the first thing to try if your car struggled to start was to give the connections a whack with a hammer to break through any corrosion. You could even give that a try.

Depending on your setup the red light may be produced by the alternator itself, and that signal also used to operate the split charge relay to connect in the leisure battery when the engine is running, and disconnect when not.

It should basically either be on (alternator not turning), or off (alternator generating proper output). Check the belt tension and condition too, if poor it might be slipping and the alternator turning but not fast enough to work properly.
 
Yeah I thought so - though I had not long pulled the leisure battery off the charger - not sure if that would make any difference to voltage readings?
The voltage drop as you remove the charger is quite rapid, so it was the alternator cranking the voltage up, after the engine started up. :)
 
Could be damp in the dash speedo unit , I had air bag warning light coming on when in cruise control . it cured it self .
 
Never mind a voltage test as on new batteries it can show 14.4 but little current,try this,park at night close to a wall pointing h lamps at high or dip,let engine idle then give a light blip on throttle,the lights should brighten a small bit,if they dont then brushes in alt may be on last legs,if lights flicker then the rectifer/regulator is at fault,most alts have them built in but some have them outside mounted in engine bay connected to alt with a plug.
 
The battery acquires a "surface charge" which bumps up the voltage when being charged, this then dies down to the natural voltage of a fully charged battery, about 12.7 V. Best way to check them is to take them off the charger, leave them overnight, test in the morning. Then you'll really know if they are actually fully charged. Small chargers, now matter how clever they are supposed to be, take time. I have a small 5A rated one (it isn't actually, I've measured it), really struggle with say a 100 Ah battery, never mind a bank of two, and maybe just cannot ever really do it. They might get them up to say 14.4V, but that's only really 80% charge, and depending on their cleverness it would take at least another four hours, probably much longer, to complete the full charge. Meanwhile the digital display might be telling you that it is already full.

Same applies when installed in the motorhome, test first thing in the morning before any charging such as solar or alternator has begun. That's the best time to get an idea of actual state of charge..

Also do not trust battery tests done with a small digital device that pulls current for a fraction of a second (otherwise they would burn out or even burst into flames), probably just from the surface charge, the plates themselves could be completely knackered, they tell you no information of any use, can't possibly do so. The good old tongs connected to a massive resistor with an analogue voltmeter were good, but nobody has them anymore, if I could find a second hand set I'd like to buy it.

My method is to connect an inverter and a 100W incandescent lamp and time how long it takes before the inverter starts beeping to warn of low voltage. It's not a precise quantitative measurement but I keep a note of the times and can see how the battery degrades.

In the past people just used to leave the headlamps on and see how long it took before they had dimmed.

That's still a useful and easy test of a starter battery, which whilst still capable of cranking the engine for a few seconds has badly degraded. It's only when you have broken down at night, might be waiting a few hours for the breakdown service to arrive, and want to keep the sidelights flashers and rear foglight on for safety, that you might otherwise discover this. Headlamps and taillights add up to maybe 120 W, 10A, so say a brand new 100Ah starter might at best last 10 hours. A tired one, still capable of cranking maybe only an hour.

The digital small handheld battery testers cannot possibly find this out.

I don't do it very often because it is nearly a 100% discharge, and the battery is put back on the charger immediately afterwards.

Also check the date code on a "new" leisure battery, I've noticed some at my local caravan/motorhome dealer that were at least 18 months old, probably never been topped up since they were delivered, good as dead. Maybe not their fault, perhaps that of their supplier.
 
Could be damp in the dash speedo unit , I had air bag warning light coming on when in cruise control . it cured it self .
That’s interesting mine came on last time I started it after it was sitting around for 3 months. Could be sulking because it heard I was going to trade it in!
 
Their is a company that overhauls them can't remember their name .new unit about £800 overhaul £150 life time guarantee ..
 
So I didnt sleep very well last night, thinking about what I may have done to my very loved van and going over all the possibilities in my mind. (I know I'm a bit bonkers, but I'm a terrible whittler when something isn't right)

This morning, first light I got up, went out there removed all four terminals, gave them a quick wipe over, straightened a couple wires out that looked like they had got a bit crimped, restripped the end of one wire as some of the individual wires were brittle and breaking ( this was a negative coming directly from the negative of the leisure to the negative of the starter battery) and reattached firmly ..... (PS Out of interest what is this weird negative wire bridging across like that - its either got to be something to do with relay system or may be connect with a 'green switch' I have on the dash which used to operate a dashboard fan and is an obvious addition by someone in her history.)

Anyway, IT'S SORTED! Yay yay! No weak and flickering battery light is coming on within a minute on idle so fingers crossed, it was just a bad earth or something fairly minor that fiddling with, has resolved! I haven't taken her out for a drive as Ive got work today.

Thanking you all again for confirming and affirming that the earths were a likely culprit here.

This year, I'm planning on going back to the Hebrides and maybe into France with my van and at present *everything* on her is working as it should! I'm so proud of my 30 year old beast - she has given me so much pleasure! :)
 
The wire connecting the two earths will be the one half of the split charge relay system.

I suspect its poor state was the cause of your problem.

Well done for sorting it out.

If it's feasible, when you return from a trip, put your leisure battery on charge for as long as possible in situ using your mains charger.

This will do a better job of looking after it than using hook up when you get back.
 

Users who viewed this discussion (Total:0)

Back
Top