Howdy and welcome from Northern Iowa.
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First, get this free Service Manual before it gets locked like the other one.

Dropbox

www.dropbox.com

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Now we will start at the most common problem.
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Have read about a few where the bolt was tight, but the wire would still move.
Honda put in a bolt that was to long.
After you check the bolts for tightness, grab the wires and see if they move.
If they do, you have to add a washer or 2 to take up the gap.
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Have read about MANY....MANY shift control motor problems.
ALL of these responses below have had your exact problem.
- - here is one
"After messing with it some more this weekend, I believe I've found the problem. I took the shift control motor off and took it apart to clean it up and looked for any signs of malfunction. Didn't really see any issues, so I put it back on after cleaning it. Started it up and put it in reverse. It seemed to function fine. Put it in drive and rode around the yard for awhile. All was fine, so I took it on a longer ride roughly 20 miles or so. Everything is running and shifting great. My guess is that the shift control motor was shorting out for some reason. Not sure what was causing that, but I ordered a new motor to put on it just for good measure. Hopefully I don't have that issue anymore."
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- - and another
"The shift motor wasn't looking to bad on the inside but I noticed the brushes and where they contact the armature were ugly enough to need attention ,just cleaned and polished gently and away we go!"
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- - another
"So I ended up doing the same and removed the shift control motor and cleaned it up. I’ve been driving it for a few weeks now and have not had any issues so for. "
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- - another
"Wow so far so good! It has not died a single time all weekend I am going to consider it fixed! Not a bad repair, sandpaper and a little aggravation and we are good to go."
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Have read where some of the older model pioneer owners carry a spare shift control motor when they go on long trails
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Next possible, injector wiring, VERY common

Honda Pioneer / Talon 1000 fuel injector wire repair kit. SXS1000

Fuel Injector Wiring seems to be a common issue. With many, the wires will pull right out of the OEM connectors with little effort. Hondas fix is to replace the entire wire harness and that could take months. This kit will help get you back on the trail in a short time. This is a custom kit...

store.hondasxs.com

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Next possible, idle air control valve

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That should keep you busy for awhile.
Post back when you find and fix the problem, pics would be great!
Maybe it will help someone else.
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Have a good day
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edit to add
reading some more, and could also be your neutral safety switch

Transmission flash code question

I have a 2018 1000/5 with very low, light duty miles and now it won't shift out of first. The "1" is blinking a 5 long and 2 short code but I haven't been able to find what that indicates anywhere. I changed the oil last summer and everything still looks good there. I did a clutch relearn but...

www.hondapioneerforum.com

 

And, let me throw this in here from another place.
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"My 2016 pioneer 1000-5 stalls when I take it out of park. Some times the gear display has a dash through it and when I put it into an gear there is no vehicle movement, like I’m in neutral. EPS light flashes intermittently also but usually stops and 3 seconds or so."
- - - and their fix
"All good now. Ended up being a bad battery. Even though it started fine it checks bad. Put a new battery in it and everything works as it should."
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Our Hondas are so voltage sensitive.
ALWAYS check voltage and connections first
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Have a good day