James when the 4EAT gearbox in the SVX recognises a big problem it defaults to what is commonly known as "Get you home" mode.
In the SVX "Get you home" mode the only available forward gear is 3 range. Reverse will work unless, naturally, reverse is part of the problem.
What you have described looks a lot like the Sonata gearbox electronics reverting to a "get you home status"
If you take the car to the dealer they will plug in the diagnostic and that will tell you what the electronics see as the major problem or combination of problems.
[BTW when I got my first SVX I drove it for nearly a year with only 3 range
It was a learning curve for me and it took a while to source a replacement box. They are not too common over here. Just saying that to assure you it will probably drive that way OK for a bit. You would still be advised to get it looked at sooner rather than later. Your gearbox might not run as long as my SVX box did, or it could have a different underlying problem]
Joe
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