2007 hyundai sonata limited

automatic transmission?
we can not guess your skills
the question is how a tech can fix it not you, you have no tools
real.
what means 3RE? (why the RE there)"
ok typo day, 3RD (D is below E) got it.
now and answer and told here 10000 times and googled 1million times. or more
check all fuses
then scan the PCm (TCM) for DTC errors then we look them up in the real service manual and amazing it tells you what to do next
as in LOTS more tests with meters and gauges.
stuck in 3rd gear means what.?

1. shift lever stuck (as in will no move.
2. in drive, car starts off in 3rd gear, now that be rare. but possible.
3. in reverse cars goes forward but in 3rd gear.
4. or coasting the transmission never goes below 3rd gear called engine transmission natural braking actions and auto downshift features. happens foot off gas pedal.
5. or means overdrive or TCC lockup failing?

A/t boxes do lots of things, even wrong, but not told clearly here.

the .pcm puts it in limp mode and it will stay in mode until light is turned off. You need to get the trouble code, repair it, erase the codes (with a scanner that retrieves the codes), and then you will be out of limp home mode.

I think your torque converter IS the problem. Because it's the only thing that attaches the engine to the transmission and it's designed to "lock up" at highway speeds for overdrive. If it locks up at idle it will kill the engine. If it locks up at slow speeds ( < 35mph ) the vehicle will lurch/buck... And if it wont move in forward or reverse I would say it's time for a new/rebuilt transmission

The transmission range switch that detects the shift lever position (N or P) could be short circuited. Replace the switch or correct the wirings.

There are few related help links related to gear shift issues:----
Click the link below:----
Gear indicator Shows "3" Instead Of "D"? http://whoisbyme.blogspot.in/2012/07/gear-indicator-shows-3-instead-of-d.html 2006 Chrysler 300c: Shifter Stuck in Park? http://technoanswers.blogspot.in/2012/06/2006-chrysler-300c-shifter-stuck-in.html 1998 Ford Expedition: Will not Shift Out of Park? http://schematicsdiagram.blogspot.in/2012/06/1998-ford-expedition-will-not-shift-out.html Car will not move when in gear?

http://repairhelpcenter.blogspot.in/2012/02/car-will-not-move-when-in-gear.html Mercedes-Benz transmission sticks in first gear? http://technoanswers.blogspot.com/2012/01/mercedes-benz-transmission-sticks-in.html Mercedes Benz not engaging in first gear? http://technoanswers.blogspot.com/2012/01/mercedes-benz-not-engaging-in-first.html Chrysler PT Cruiser only goes in First gear?

http://howtobyme.blogspot.com/2011/11/chrysler-pt-cruiser-only-goes-in-first.html

Car is stuck in park and the shift will not move?

http://howtobyme.blogspot.com/2011/08/car-is-stuck-in-park-and-shift-will-not.html

2007 Ford Expedition: How to shift car in neutral with Dead Battery http://www.howtorepairguide.com/2012/11/2007-ford-expedition-how-to-shift-car.html 2002 Nissan sentra will not go out of park mode? http://technoanswers.blogspot.in/2012/02/2002-nissan-sentra-will-not-go-out-of.html Nissan Sentra stuck in park? http://technoanswers.blogspot.in/2012/02/nissan-sentra-stuck-in-park.html Car will not come out of Park?

http://howtobyme.blogspot.com/2011/11/car-will-not-come-out-of-park.html

Automatic transmission will not go into high gear?

http://howtobyme.blogspot.com/2011/11/automatic-transmission-will-not-go-into.html

Car won't downshift sometimes?

http://schematicsdiagram.blogspot.com/2011/12/car-wont-downshift-sometimes.html
Buick Park Avenue: Transmission will Not shift into drive?

http://schematicsdiagram.blogspot.com/2011/12/buick-park-avenuetransmission-will.html
No First gear Starts In Second Gear http://www.howtobyme.blogspot.com/2012/07/no-first-gear-starts-in-second-gear.html Ford Taurus won't shift from park? http://schematicsdiagram.blogspot.com/2011/12/ford-taurus-wont-shift-from-park.html 2006 Ford F150: Will Not Shift out Of Park? http://technoanswers.blogspot.in/2012/06/2006-ford-f150-will-not-shift-out-of.html Car Transmission will not go into Park mode?

http://schematicsdiagram.blogspot.com/2011/12/car-transmission-will-no-go-into-park.html
1998 Chrysler Voyager: Transmission Problem? http://howtobyme.blogspot.in/2012/06/1998-chrysler-voyager-transmission.html Shift indicator directly goes to 2nd when key is turned ON?

http://schematicsdiagram.blogspot.com/2011/12/shift-indicator-directly-goes-to-2nd.html
Third gear missing and engine losing power?

http://schematicsdiagram.blogspot.com/2012/01/third-gear-missing-and-engine-losing.html
Chevrolet silverado has whining sound in gear?

http://technoanswers.blogspot.com/2012/01/chevrolet-silverado-has-whining-sound.html
2002 Chevrolet Avalanche Z71: Gear shift Issue? http://whoisbyme.blogspot.in/2012/06/2002-chevrolet-avalanche-z71-gear-shift.html Hard to shift gears on Manual transmission?

http://technoanswers.blogspot.com/2012/01/hard-to-shift-gears-on-manual.html
Car hard shift at slow speeds?

http://technoanswers.blogspot.com/2012/01/car-hard-shift-at-slow-speeds.html
Transmission-Hard To Down Shift http://technoanswers.blogspot.in/2012/07/transmission-hard-to-down-shift.html Automatic transmission shift lever hard to move on cold mornings?

http://technoanswers.blogspot.com/2012/01/automatic-transmission-shift-lever-hard.html
2000 Nissan maxima shifts hard?

http://schematicsdiagram.blogspot.in/2012/02/2000-nissan-maxima-shifts-hard.html
Vehicle noticed sluggish delayed shifts while driving?

http://schematicsdiagram.blogspot.in/2012/03/vehicle-noticed-sluggish-delayed-shifts.html
2007 Hyundai Santa Fe: Will not Shift out of Park Mode? http://schematicsdiagram.blogspot.in/2012/06/2007-hyundai-santa-fe-will-not-shift.html

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These will help.
Thanks.

your transmission is toast
sorry bout humanitys no luck program hopefully ur bone dry on fluid i wont assume u did to save face

It sounds like The transmission goes into something called "Safe Mode" Which prevents any harm in coming to the transmission from usually a low fluid level. Follow proper procedure for checking your A/T fluid levels. And only use dealer A/T fluid. A universal fluid can ruin your transmission because Hyundai takes a special synthetic.

I’m happy to assist further over the phone at https://www.6ya.com/expert/cameron_6665f74c5d46fc23

There can be play inthe shift levers, play in the connecting links.
One there is play then the levers will not move firmly and so it will not have the postion correct to shift the notches inthe gearr box.
So you may have to see if there is any nylon washers or links that are loose and needs a tightening, if the shift lever shows a wobble then it needs this correction.

If I understand you correctly, you have ALL forward gears working, but reverse doesn't?... then the problem is in the transmission itself or the linkage on the trans linkage into reverse.