Yeah not a bad idea, i think the aux battery also helps as the power to the systems isnt totally lost too. I did the little battery first and then the main (different weekends mind!) Id always have one of them connected to avoid needing an resets but the jury is out on if it is required or not. There is a post somewhere that is from a service bulletin (not for our eyes I guess) that says about resetting but I have a tame ex LR guy I used for the my old Sport and asked him about it and he said its not something he would do unless there were faults and errors present before the change or after fitting the new one there are errors.

I will continue as is for a bit and if I get any problems and have to use the GAP Tool ill post back, but from what I can see I dont think it is needed.

When you say full size how big are you talking my one is 195 70 R20 and yeah it was pretty heavy to lift out but marginally easier than the battery as its got stupid little handles.

I like the idea of the jump leads its a good thougt especially for the guys who have the capacitor on the 2017 on models If a jobs worth doing, get a someone who knows what they are doing to do it!

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Probably a dumb question but if I just wanted to give my current battery a full charge over night will I have to do any of that reset stuff the next day when I put it back in?

Nope just put the charger on the points under the bonnet (hood) and charg away, depending on the type of charger you have leave until full anc check every now and again, dont charge the battery directly.

The jumper points are on the right hand side one has a cap on it. The more amps the charger can put out the faster it will charge.

If you are having to charge the battery up once a week say then its probably best to replace it as it means you can leave the car whilst out and about and not worry if it gonna start when you come back!

The little battery I belive can be charge directly (I did mine before I changed it to fault find it) the aux battery charges through the main battery so my guess is until the main battery has been charged enough the ECU's wont push a charge to it so not sure if just charging the main battery over night will top up the aux one after I suspect not as this is probably managed by the ecus in the car when the alternator is the primary source of electrcity.

I shouldnt worry about the resetting as I said I havent done it and have no issuse I think its only needed if the car was in a state of error with loads of lights on the dash! Probably a good charge and quikc drive and then a battery swap woudl negate the need for resetting with a gap tool or dealer, I confirm I have not had to reset mine at all If a jobs worth doing, get a someone who knows what they are doing to do it!

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I have the 21" wheels & mine is a full size wheel, your pic looks like a space saver & found that I could not get it lifted out of the well without "lifting tool" , but as it clips into the rear aperture, the centre of gravity is basically above the wheel centre so there is no inclination for it to swing outwards. It is just so unwieldy even with that tool

thats a then yeah mine is only 195 wide so not really gonna be any good on a green lane expo but, on the road maybe!

I keep an air compressor and some slime in the car just incase as its enough to get home on. At least the spare is inside the 1st gen were a pain to get at when its 2 degrees and heavy rain (the RAC would always get a call!)

dunno how my 21's would fit back in the boot I guess that what the little spacer is for where the full size wheel wouldnt need it as the boot floor would sit on it with no gap!

Id still rather have a spare than just the tyre foam kits as sods law when you hit a pot hole or something an buckle or damage the rim you will need a wheel the foam just isnt gonna cut it! If a jobs worth doing, get a someone who knows what they are doing to do it!

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Hi, i swopped my main battery over today and found a none connected wire? there are two wires going to the earth lead (Blue/Brown and Green white) these push into a clip attached to the neg terminal, but i found on the other side of the battery just dangling loose a 2 wire (brown/white and black/white) connector but can't seem to find where it goes? Any ideas? Please see photos

I asked this question a while back. See link

https://www.rrsport.co.uk/forum/topic55483.html

Great thanks for that thought I’d disconnected something I shouldn’t have !

I dont remeber seeing one of those in mine that said it may have been part of the cluster on terminla cable and as it wasnt connected I didnt think about! If a jobs worth doing, get a someone who knows what they are doing to do it!

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I charged my battery over night by connecting it to the connectors under the bonnet, have driven it past few days and start/stop hasn't worked once 😞 any ideas why or is it just ? Thanks for your help so far

id say the battery is on its way out mate, i have my old one indoors and its been on charger for over 24 hrs and still not showing as full. If the batteries get really low I dont think they like it and even a full charge wotn bring them back (that is ono older batteries) most of these batteries have a life of around 5 yrs ish and you can get more out of them but for the small cost i decided not to mess about and just swapped them out and now ASS is working and I have peice of mind that if I leave the car say in airport parking (not that we are going anyhwere at the mo) it will start when i get back

Yuo could buy a ctek mx5s battery cahrger and conditioner and give that a go but that is liek £60 and whilst handy still might not repair the battery as its probably too far gone now, basically the battery might still hold 12.2 ish V but I suspect over the years of start stop ing an everything else and psosibly being let run down on occasions due to short journies in summer with AC and fridge etc... the battery has lost some of the amps (the punch it has) and doesnt have enough to keep firing up the enigne and all the other stuff anymore so the ecu tells the system dont use the ASS as the battery doesnt have it in it anymore.

Id just swap the battery out and be done with it, also ASS will only work when the cars has enough power to use it, so if AC is onl or heated seated or demisters etc.... then the system might not turn it on due to other more requried features being used.
In a sesne ASS only come on in a perfect world where you are warm the wearther isnt bad and butterflies are floating out of your exhaust! If a jobs worth doing, get a someone who knows what they are doing to do it!

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Hi guys, very informative post this. Well done! I’ve been having some battery issues during the cold weather where I’ve had to start the car with a portable boost pack. I’ve decided to replace the both batteries for a quick fix. I took the right hand panel off in the boot to reveal the Aux battery... to my shock there is nothing there! Does this mean I have a capacitor? Or has someone robbed my battery haha. FYI I don’t recall the stop start ever working in nearly two years. Please see pic of where Aux bat should be.


[img] 2016 Yulong White L494 AB/DYN 3.0SDV6

yep that is the capacitor on that little plinth where that batt would normally go, I think the start stop uses the main battery anyway the aux bat or cap just supply power to all the other stuff when the enigne isnt running so stero and lights etc...

the ASS doestn come on if I get in mine from cold and then have the AC and heated seats on etc... it waits for the car to reach temp first beign it becomes active, I also have the fuel burn heater so when i start up the car get warm quite quick as it fires that up to help heater the car up quicker and I think that can run without the engine on anyway.

Use the link for the main battery just swap that = its cheaper as you only need the one battery!

Good luck its a pretty simple job just search on here for my other post on how to fit the main one If a jobs worth doing, get a someone who knows what they are doing to do it!

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Spot on pjbracer thanks for all the info... battery ordered! Just another quick one, I googled that part number in my pic and comes back ‘comfort control module’ is that the same as the capacitor? Sorry if I’m being daft. Haha

Also interesting that most people say capacitor was not added until 2017 but mine is 2016 model. 2016 Yulong White L494 AB/DYN 3.0SDV6

Cant be sure exactly when the fitted them and maybe if yours was a 2016 car that was one of the first to get it perhaps as it was one of the last 2016's prior to the 2017 going into production maybe!

I think comfort control might be right as the cap runs all the nice stuff like the fans and stereo/tv lights and windscreen when the engine isnt running and allows that stuff to stay working even if the main battery is a bit low but it would never have enough beans to start the car as most need an 850CCA batt for that initial kick so if the main was really low the car starts to shut down systems to allow the car to run in its most basic form to allow you to drive it, hence a low batt can cause all sorts of errors and dashboard lights and horrifying message saying blah blah your liver is being disabled!

I think the fridge also uses that too so it can all remain on whislt the ASS kicks in or means there is more power available from the main battery where there are lots of things all requiring it.

ASS doesnt start immediatley when the cars has the climate set to max in winter or summer I guess so the cap or aux provides support to other things classed as non essential, some guys on here have been running around with the aux battery dead and not even noticed, I bet if you sat in a car park waiting for her indoors to finish gassin you could sit and still use all the stuff in the car without the engine going and not drain the main battery.

The main batt fit is pretty simple so no biggy just a bit awkward getting them in and out mainly cos they are heavy and they are kinda at arms length when lifting them!

Good luck If a jobs worth doing, get a someone who knows what they are doing to do it!

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