Check Engine code 65620.

@Tripod will likely be in here soon and post up. I have the manual, but I'm at work and it's at home. If you are on the side of the road now, try cycling the key on (wait for full sweep of gauges to complete) and then back off 3 times. Sometimes this will clear it (still be in memory, but resets to correct the problem unless it reoccurred again). It may come back, or it may be a glitch that was a one time only. Once we get the code checked, we'll have a better idea of what needs done.

Edit: didn't realize you already had looked up the code. I found it, and it said just what you mentioned. Like Tripod, I can find them, not necessarily be able to fix them. I would think this has to do with the stability/traction control/anti lock brakes (guessing sensor going bad). Only a guess though. Watching to see the more knowledgeable on here to reply.

First thing I would check is the battery cable tightness on the battery post. Seems that a lot were found loose and caused issues.

LC

May be moisture in the throttle position sensor plug.

Everything I can find that has 5 volt items...related to throttle...

i think a trip to the dealer may be a good route. I think @Ruptured Duck had this issue Less than a year ... Freaking ECU issue is back, code 065620

Did you check the battery for the cables being tight like @LargeCar mentioned? I took mine in for a warranty issue shortly (pun intended) after getting it, and luckily I was about to do the battery upgrade to the Optima full size. My terminal was only finger tight, and with the work I had done I would expect the service dept to have had the cable off. I've heard of them loosening up over time. You are right, "Help" might have gotten more response. I know that if I see engine code in topic, and very many have answered, I've moved on before thinking that you already had the code.

Hard to diagnose many things like this over the internet. @Slingrazor @TravAZ, either of you able to help? Perhaps know someone else that might shed light on this?

You could try to reset the electrical system by disconnecting the battery ...

If that doesn’t work the dealer will have to run diagnostics with the Digital Wrench.

Quote from Ross

i think a trip to the dealer may be a good route. I think @Ruptured Duck had this issue Less than a year ... Freaking ECU issue is back, code 065620

There was a lot involved with our first SlingShot. That thread kind of explains that they never told me the cause. In my case Polaris took care of us. To answer the question before it's asked I have no special contact or method to work through the warranty process. Not trying to sound mean, just telling how my process went.

Haven't dealt with this personally yet (knocking on wood).

I would check the throttle position sensor connection at the throttle pedal itself and check the connection at the actual throttle body on the intake. Unplug them and make sure all of the pins are straight and re-plug them in after putting some dielectic grease on the connections.

It is also possible that something is shorting out in the harness too. Hopefully not.

It happens to the best of manufacturers. In my case it was a long process that finally reached a point where all options had been tried.
Ours was a 2015 built in October and was the 887th off the line. We believe it might have been caused by a short somewhere deep in the wiring. At it's final failure it just stopped firing on all cylinders when it would re-fire and then it just finally would not start.

This past weekend I was at a high end auto dealer and noticed a brand new model in the service bay totally stripped down. I'm talking to the body shell and everything removed. Basically it had an electrical issue that could not be found in the normal manner. The manufacturer contracted the dealer to totally stripped it down to find the fault. Ended up being a very, very, very small nick in one of the main wire harnesses that feed several major subsystems. The dealer was well over $15,000 in billed labor hours.
I was amazed to the extent the manufacturer went to find a fault that had not shown up on any other of the models produced.

Can I ask a question that is probably totally unrelated, but what does a tipping sensor do? Are they commonly found on motorcycles? Why would the Slingshot have one?

The tip over sensor will shut off the fuel pump as well as the engine if the SS gets upside down.

I moved mine to another location but made sure that it remained mounted in the correct position.

And yes they are standard equipment on all motorcycles these days.

Thanks @Ghost! Wonder if maybe those go bad and are overlooked when throttle response/engines die?

There were some Slingshots affected by the key getting water inside it. I can't exactly remember what happened when it did. But I remember some saying they had to remove the key cylinder and have it replaced. I even think someone figured out they were installed upside down. Probably not your issue. If someone can remember what I'm talking about post it below.....

They can and do go bad on occasion but normally they are either good or bad. That being said, if someone moved one like I did and didn't get it mounted correctly it could cause it to shut off when cornering hard in one direction and not in the other.

early on the ignition switches were installed upside down with the weep hole pointing up.
That was the water issue