FL2 XS TD4.e economy mode?

So, the Rav4 turned out not to be as good as I'd hoped, still used the FL1 more, which was more economical!
Did a silly thing, test drove a FL2, heck was I won over! So second one seen, offered fair P/X on the Toyota, so FL2 has been mine now for a few months, well made up!
Comfy, handles OK, yet to tow the caravan away due to lockdown, but everything seems just fine, and 36.6 average mpg not too bad either!
Just looking for a bit of guidance over economy mode, really thought this should cut in more after my commute on motorway and then start / stop on the Birmingham ring road!
Gut feeling, battery! It's still the original fitted, 2010 era, am I right in thinking that if battery is "decaying": from ECU registered values that the start / stop doesn't kick in as self preservation in case battery too low to start?
I'm considering new battery, probably Halfords own AGM (Yuasa made) with 5 year g'tee as cold crank can seem a bit slow, but not looking to spend unless I have to!
Any thoughts appreciated?

Had an OEM battery fitted by the local Land Rover dealer and didn’t strike me as too expensive. You really don’t want to skimp on a battery if you want it to be reliable. Had the glow plugs checked at the same time. My previous battery checked out OK but just could not deliver the current for a cold start on the winters morning.

Hi Richard.
Check to see if you only have the short earth lead going from battery to inner wing, if so then add another earth cable direct to the starter motor bolt, you will get better cold cranking and FL2 will start better.

Arctic2 said:

Hi Richard.
Check to see if you only have the short earth lead going from battery to inner wing, if so then add another earth cable direct to the starter motor bolt, you will get better cold cranking and FL2 will start better.

Click to expand...

Arctic2, thanks for that and comprehensive pics, appreciate that few ohms can make a difference.
I take it the new earth cable was a breaker specail? Is that a standard +ve starter motor cable?

Halfords sell battery cables. They may have one sized to fit.

Well, not having to go there! Both inner wing and bell housing have earth straps, so can't better what I already have!
Looks like bullet biting time and just get a new battery.

Richard Snow said:

Well, not having to go there! Both inner wing and bell housing have earth straps, so can't better what I already have!
Looks like bullet biting time and just get a new battery.

Click to expand...

Hi John.
I presume you are referring to this earth for the bell housing? well my car as that too, quite a few of us still added the earth direct from the battery to a bolt on the starter.
1

I used a strap I had off a Rover 75 which was in my spares box but they can be purchased I think you need one at least 3ft long.
2

Worth a read.
https://www.freel2.com/forum/topic16694.html?highlight=earth+length