Hi i have Hyundai Elantra 2007 its EPS light

The electronic power steering (EPS) Warning Light is located on the instrument panel. This light illuminates when the EPS is malfunctioning. When this light is lit, your steering may be a little heavier, and you should schedule an inspection as soon as possible. Tip The EPS Warning Light briefly illuminates when the car is first turned on. The light is only a problem if it stays lit for an extended period.

The electronic power steering (EPS) Warning Light is located on the instrument panel. This light illuminates when the EPS is malfunctioning. When this light is lit, your steering may be a little heavier, and you should schedule an inspection as soon as possible.

Visit the on-line store, known as reliable-store, they have the repair manuals. I'm sure you will get the solution of your problem.
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Well, you probably know it's the power steering.
Do you have any trouble with that? Sluggish? Harder to Turn?
That light is supposed to tell what you feel is really an issue. And you probably need to get that fixed.

EPS- Electronic power steering warning light. is there any steering problems ? Light being on means there probably is a trouble code in the EPS module .

Same as ALL vehicle issues

Put a scanner on it & check for codes
& look at data,don't use it like that, until
you know the issue

Have a shop drive it for 25 miles & record data
& wait for it to act up,then diagnose the problem

why EPS lights still on while driving and did this problem during driving?

EPS is Electronic Power Steering.

When the light comes on, it is a warning that the Electronic Power Steering system is having a problem.

The increased force you have to use, is because the EPS is not assisting you as much as it was before, if at all.

Here is a link to a video explaining the basic operation of the electronics at youtube.

Sometimes (few) a fault in the wiring loop causing it to short on the steering column and turn on EPS (Electronic Power Steering), check it and scanned for know if some additional fault code is stored there.

Keep us updated.

Your Electronic Power steering has an issue - have a shop look at it for you before it fails completely.