Sounds like a good start, but I might be able to shed a little more light on your issue... :dontknow:
Back a while, the 8 or so year old original battery in my 2013 RT started to get tired, working to start the engine, especially in the cold, so I replaced it. Purchased a new (higher rated) battery; charged it for 12 hours before installation; no worries doing the job, altho I did have a little trouble keeping the Negative lead out of the way as I slid the new battery in & I hadta move that cable around a little... (remember that, why becomes clear later!

) Took it out on short a test ride, and all seemed fine. It was a luverly day, the sun was out, not too hot, we had nothing scheduled for the day; sooo, I took the Child Bride out for a longer ride; a bit of faster stuff to start with, then lunch & gas up before heading home via the twisties - yep, the Child Bride's a Rev Head too!

hyea:
BUT, once we hit the twisties, the trouble started!! Exactly as you describe, halfway thru a corner it'd feel like the steering locked up for a second or two - dive in too hard & it made for a real bum-pucker moment as the steering just seemed to jam & leave us drifting out of the turn at speed!! Slower, it'd be nowhere near as confronting, but it'd still be there, popping up every now and then! Suddenly lurching halfway thru a corner before coming back & working fine. Now I know very well what Nanny intervention in all its forms feels like, and it definitely wasn't that, but it did really feel like the DPS was either locking up or taking control & trying to go the wrong way. Nothing permanent tho, not as if the DPS had failed completely so that the steering just became a whole lot harder all the time; rather a seeming lock-up or take-over every now and then, but always when the steering was under load/halfway thru a corner/coming off a bump; it happened turning either way, so it wasn't tires; and it was getting worse.... :shocked:
After a very tentative trip home, I looked at
EVERYTHING I'd touched that morning, thinking it was most likely the last thing I'd touched that'd be causing this issue, and that last thing was the battery. But it'd been good for all the trip out, almost 150 miles of fairly high speed straights & sweeping curves, so surely not??? :dontknow: It was only once we hit the bumpier, twistier roads, with lots of direction changes & 'G' forces.... could the battery be falling out, or had the DPS failed internally?? The battery still looked good, tested well, secured solidly in place, all the terminals tight, star washers firmly gripping, nothing moving or loose; I even checked how tight the cables were in their respective terminal ends.... and
THEN it hit me - that bloody Negative cable that'd been flopping around and getting in the way!!
I'd checked the
BATTERY end, hadn't I?! But I'd completely ignored the
OTHER end of that cable, and I'd been rattling the battery end a fair bit!! The other end is buried waaaay in behind the Left Front Wheel, deep in the guts of the machine, right where the DPS is mounted on the Main Spar of the Frame, and there's a major Earth point there too; so there's a lug soldered onto the cable that's meant to be tightly secured to a clean & shiny patch of the frame, allowing it to serve as the Main Earthing point for the Battery
AND the DPS!! So I started digging, wheel off, work light into the tunnel, following that Negative Cable. And when I finally reached & checked the bolt & Earth connection, it felt nice & tight, looked like a good connection onto the frame too... :dontknow: Went to grab the cable & rattle it around a bit just to be sure to be sure, only just by
touching the Negative Cable I knew I'd found the culprit!! The solder holding the cable into the terminal/lug that was bolted to the frame had given up, and while the terminal/lug was tightly affixed to the frame, every lurch, bump, or rattle meant the cable would move in the socket and so not Earth the battery
OR the DPS!!
THAT was why it was intermittent, and mostly on corners/bumps/under load! :gaah:
It took about an hour to fish the cable out far enough to clean & re-solder the terminal/lug onto the cable again; maybe another 10 minutes to get it all back in place and tightly secured again; then a solid couple of hours of riding all the local twisties & bumpy roads I could think of to convince myself that I'd truly fixed it! And I had!

hyea:
So I reckon your problem
DOES sound very much like a dodgy DPS and not really VSS/Nanny related, and while yours may not be a dud joint &/or broken solder, have you replaced your battery lately, or even just connected anything to the battery terminals?? Are those battery terminals tight, and if they are, will the cables move in the sockets of the terminal/lug ends at all?? Have you checked the
OTHER end of your battery cables too, and checked to make sure the terminal/lugs are both securely soldered/crimped onto the cable ends and tightly fixed to a clean, bright, & bare section of the frame?? Cos if you haven't, then like me, you juuust may have found the source of those particular steering problems... :thumbup:
Good Luck! :cheers: