[JohnnyJaguar]

Dear friends, I’ve had the battery not charging light come up. Icarsoft points to secondary battery and alternator shot. My CTEK is unable to charge the secondary s/s battery so for sure that needs replacing. Local garages have told me that I need Jag dealer or specialist to handle the job as they need software to integrate the new battery. Is this correct? This surprises me and I cannot get booked in for several weeks! Thanks all.

 

[Gav]

Replace it yourself, doesn’t need anything else.
Don’t use local garage again!

 

[JohnnyJaguar]

Replace it yourself, doesn’t need anything else.
Don’t use local garage again!

Thanks Gav, just worried about cocking up the bms

 

[Gav]

Thanks Gav, just worried about cocking up the bms

It’ll sort itself out, but your icarsoft might be able to tell the car it’s got a new s/s battery

 

[OBC John]

Wot @Gav said.

It winds me up and depresses me in equal parts either how deceitful or ignorant garages are (including Jag dealerships).

 

[Gav]

If you are doing it yourself though please follow the proper procedure, search for it on here if not sure…..

 

[OzXFR]

You may have both a duff battery and a duff alternator.
By battery I mean the main battery not the auxiliary/second/small/SS battery although that is almost certainly duff as well.
The cause of duff battery/ies may very well be a duff alternator so that is the first thing to test/check.
Then check the main battery for charge and condition, if it's a bit low (and the alternator is good / fixed / replaced) it may well fully recover with a charge. If not then it is time for a new battery
Best bet is to take the car to a good auto electrician to properly test the alternator and battery.
No need to worry about the secondary battery as it doesn't effect anything other than the SS system but once you have a healthy alternator and main battery it may recharge and fix itself.
Or you can disconnect it or even completely remove it from the car with no ill effects.
If the secondary battery is beyond saving and you really really want a working SS system then you can replace it with an Exide EK151, the OEM battery is simply one of those with a JLR sticker plonked on it.

 

[Phil1]

Given that the secondary battery doesn't really cause any issues if you disconnect it (other than disabling the stop start), then it makes me think it's far more likely the alternator itself is duff if it's bringing a not charging fault up.

 

[sockpet]

Had the same thing a couple of years back with same message, was the start stop battery that went flat, but often burns the alternator out when it happens (According to local garage).

When my stop start battery failed, Tayna did the stop start at half the price of ECP, I ended up replacing both batteries for about £170 and the alternator was about £250. It's probably double that now with inflation. I also bought a BMS module off ebay for £27 just in case.

I got the garage to swap the alternator as you have to jack the engine up to get it in and out and couldn't be arsed to do it, they charged 3 hours labour. I am fairly sure they never reset BMS and I had no issues, but in all fairness the original main battery still had over 12v and even a year later after sitting on my garage floor it still had charge so I probably didn't need to change it..

 

[ninjag]

Alternator is a bit of a pig to do. If taking your time for the first time it's an easy 3-4 hours, for the local Jag indy who knows what they are doing it's still over 2 hours quoted. I'm sure genuine OEM Denso ones are over £500 and worth going for from what I've gathered.

 

[JohnnyJaguar]

Thanks for the advice all. One Jag dealer has quoted £660 for the alternator and £170 for the s/s battery - that’s just the parts, no labour added in yet! Another won’t touch the car without doing their own diag, and they want £350 for an hours diag! This is doing my nut, car is sat for a week now.

 

[Beevee]

Your icarsoft can tell you what the battery voltage when the car is running
Check the voltage
If it’s around 14.5v, your alternator is fine
Your small battery - which incidentally isn’t the stop/start battery, it’s the big one - is probably duff if your getting around that voltage

 

[PeteA]

Be wary of after market alternators, several stories of them not working properly/not lasting long.

Not that genuine ones are impeccable mind, as you now know...

 

[Phil1]

Be wary of after market alternators, several stories of them not working properly/not lasting long.

Not that genuine ones are impeccable mind, as you now know...

I'd agree with that.

I would also see if you can do a bit of research and see if you can source (a genuine) one from somewhere other than Jag themselves, as essentially they'll probably add about £200 just for the fun of it.

 

[xf_phil]

Thanks for the advice all. One Jag dealer has quoted £660 for the alternator and £170 for the s/s battery - that’s just the parts, no labour added in yet! Another won’t touch the car without doing their own diag, and they want £350 for an hours diag! This is doing my nut, car is sat for a week now.

The small battery at least on my car is made by Exide, I replaced with a EK151 e.g. this one from tayna which retails at <£50
An easy job, hopefully your icarsoft will reset the BMS ( I know at least some models will )

 

[Gav]

Your small battery - which incidentally isn’t the stop/start battery, it’s the big one - is probably duff if your getting around that voltage

the small battery is commonly called the s/s battery as it’s the one that keeps the electrics alive whilst the engine is shutdown but the big battery starts the car.

 

[JohnnyJaguar]

The small battery at least on my car is made by Exide, I replaced with a EK151 e.g. this one from tayna which retails at <£50
An easy job, hopefully your icarsoft will reset the BMS ( I know at least some models will )

Cheers Phil, any pointers on how icarsoft can reset BMS?

 

[cutlea01]

It's one of the service menus. Once plugged in, car and model selected, you'll have an option to enter service items, rather than diagnostics. It's in there. Sorry for being vague, this is from memory!

 

[xf_phil]

If it were me I'd probably replace both batteries, and only if the warning message still persists change the alternator ( just don't keep running it or you'll damage the new battery too ). If the alternator has failed, chances are the battery will be drained to the point of permanent damage anyway, they're not that expensive ( as long as you don't go for a Jaguar branded one), for example I used an Exide EK950
Be sure and look up the threads about letting the car shutdown properly before disconnecting the large battery though, as otherwise you're much more likely to run into the dreaded CJB/BCM issues.

 

[JohnnyJaguar]

If it were me I'd probably replace both batteries, and only if the warning message still persists change the alternator ( just don't keep running it or you'll damage the new battery too ). If the alternator has failed, chances are the battery will be drained to the point of permanent damage anyway, they're not that expensive ( as long as you don't go for a Jaguar branded one), for example I used an Exide EK950
Be sure and look up the threads about letting the car shutdown properly before disconnecting the large battery though, as otherwise you're much more likely to run into the dreaded CJB/BCM issues.

thanks a lot Phil, sound advice to look at bats first, I’ve had the CTEK in the main battery and seems ok, the secondary is shot. I’m ordering the exide - however I’m not so confident in removing the old s/s battery. What is the wiring indicated on highlighter on the image below? Is there a procedure for removing this small battery and reverse for installing new? Thanks!