START / STOP STOPPED!

[Myer]

I fitted a new Varta AGM battery to my five year old F-Type R Coupe, all fine reset rear tailgate, widows and clock.

The only thing that no longer works is the dreaded Start / Stop function, I am very please as personally as I loath it!

I have been told that should I want to reactivate the Start / Stop, I would have to get a Jaguar service dealer to reset the BMS. apparently they have to sync the battery to the eco system It sounds ridiculous!

Has anyone had personal experience of this situation, does it only occur with a new battery, maybe it can remember the original fitment and functions "correctly" without pairing provided there is no battery swap. Other than that is there a downside to not syncing? One Forum member suggested that after a period of time it might reset itself.

[scm]

Is the new battery fully charged? I believe they usually come with less than a full charge, and if the voltage is low that might stop the stop./start from operating.

[Myer]

In truth I haven't checked the voltage but my dash and display screen are now so much brighter than with the original battery. You might be right and time will tell.

[Tel]

In truth I haven't checked the voltage but my dash and display screen are now so much brighter than with the original battery. You might be right and time will tell.

You might find that they have defaulted back to maximum brightness since the reset.

Also, the good thing is, most of us that have had Stp/start didabled from birth no longer need the expense of AGM batteries!

[Myer]

Good point on the brightness however prefer it bright.

On the main point does anyone know about resetting the BMS? Which I assume stands for battery management system

Apparently the dealer has to sync the battery to the eco system. Anyone experienced this situation

[Chrissyg]

I've disconnected and changed the battery in mine several times and haven't ever had to "sync" the battery to the eco system. Doesn't make any sense to me. I'd get the battery fully charged and see if that sorts it - all my stop/start issues not working on my old V6S were down to battery condition - and I had some serious stop start issues due to corrosion of ECU's in the boot due to water ingress.

[Myer]

The battery is now at full charge, there has been no water ingress and according to the USA Forum and my local dealer it does need to be synced / BMS reset.

[Tel]

Allegedly - Part of the diagnostics for replacing the battery includes resetting the management system. It lets the system know that for example the replacement is a different Ah, and adjusts the charging output from the alternator accordingly.

Not many people have bothered, and I know folk that are using tiny Li Ion batteries without resetting the BMS, and they have had no ill effects.