The light on the overdrive is flashing always and don't change the gears on the overdrive,

to start with there is nothing wrong with the ransmission
It is all electronic faults
the transmission is constant mesh so ratios are not manually changed by done by servos and solenoids
the fault code refers to the TR sensor that can be changed out , the hard shifting is probably dirty oil and the changing between ratios a problem TCM or wiring harness connections
if the transmission oil has not been changed in the last 60K miles , that would be a good place to start, then have the auto transmission professional service center where you are having the oil change done, check out the servo/ solenoids operations

That is what is called limp mode does the transmission shift gears real hard you need to Pull transmission codes and see what is the problem

When the a transmission solenoid is malfunction, in most cases the problem is not the electrical part of the solenoid; the problem is foreign material obstructing the mechanical function of the solenoid or the flow of the fluid through the transmission valve body. If the transmission fluid is very dirty, it is recommend changing the transmission fluid and if possible removing the transmission pan for further diagnosis. Excessive debris or metal particles on the transmission pan could be an indication that there is a transmission mechanical failure and that the transmission will need to be rebuilt or replaced.

Read more: http://engine-codes.com/p0745_nissan.html#ixzz2juUvQKpy

For Automatic transmission problem,click the link below:----Overdrive light in the dash blinks? http://repairhelpcenter.blogspot.com/2012/01/overdrive-light-in-dash-blinks.html
--------- Automatic transmission troubleshooting:----

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

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Automatic transmission shift lever issues?-------

http://technoanswers.blogspot.com/2012/01/automatic-transmission-shift-lever-hard.html

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AUTOMATIC TRANSMISSION FLUID LEVEL? --

http://schematicsdiagram.blogspot.com/2011/07/how-to-check-automatic-transmission.html

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AUTOMATIC TRANSMISSION FLUID AND FILTER?

http://schematicsdiagram.blogspot.com/2011/07/how-to-change-automatic-transmission.html

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Transmission fault light on car dash?

http://schematicsdiagram.blogspot.com/2011/12/transmission-fault-light-on-car-dash.html

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Transmission shifting problem?

http://schematicsdiagram.blogspot.com/2012/01/transmission-shifting-problem-on-toyota.html

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Transmission Slips out of 2nd gear?

http://repairhelpcenter.blogspot.in/2012/02/transmission-slips-out-of-2nd-gear.html

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OD light flashing and transmission fluid leaking?

http://repairhelpcenter.blogspot.in/2012/02/od-light-flashing-and-transmission.html

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Why Transmission fluid leaks near radiator?

http://repairhelpcenter.blogspot.in/2012/02/transmission-fluid-leaks-near-radiator.html

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Transmission fluid leaking?

http://technoanswers.blogspot.in/2012/02/ford-windstar-transmission-fluid.html

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****** wont go in reverse?

http://technoanswers.blogspot.in/2012/02/dodge-neon-wont-go-in-reverse.html

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Automatic transmission will not go into reverse?

http://technoanswers.blogspot.in/2012/02/dodge-automatic-transmission-will-not.html

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Transmission is making buzzing noise?

http://technoanswers.blogspot.in/2012/02/transmission-is-making-buzzing-noise.html

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This will help.

Thanks.

are you missing 2nd gear too? shifting 1 to 3? If yes, 2-4 gear band is bad. common issue.
just google cd4e no overdrive and see comments. You have 6/60powertrain warranty or if extended service plan even more coverage. call dealer with VIN to se if under warranty

TRANSMISSION SLIPPING NOT ENOUGH FLUID IN TRANSMISSION OR NEED A TRANSMISSION FLUID FILTER CHANGE.IF YOU HAVE PROBLEM WITH OVER DRIVE.CHECK ENGINE LIGHT WILL FLASH ON WARN YOU PROBLEMS WITH TORQUE CONVERTER OR 3 - 4 SHIFT VALVES SOLENOIDS.

hello subir. This is the over drive function. someone may have accidentally pushed this button so to turn it off you will have to find it and push it again. there is a Overdrive button somewhere on the shifter. It is probably on the side of the actual handle or down near the 4-speed gear numbers, sometimes even in the end of the shifter..

O/D off is NOT a big problem at all- you just don't want to use it all of the time because it runs your engine a lot harder because you are always in a lower gear. That would be used if you were driving up a big hill, for example, and don't want it staying in the highest gear. It gives you more power in circumstances like that

This is indicating an issue with the transmission that should not be ignored. The flashing light was designed to annoy you into action. Waiting could cost you a lot more money. I would get the error codes by asking my local shop to get them, or many chain auto stores offer free code reading, just ask. I was at AutoZone a few weeks ago and got the codes, and they printed them off for me, in addition to recommendations as to the cause.
Best case scenario is just a reset is necessary (computer perhaps). You don't want to be stuck on the side of the road, so it's good to find out.

Good luck and let us know how it turns out.

The best case scenario is that your overdrive switch is malfunctioning, and simply needs to be replaced, along with flushing your transmission fluid and replacing the transmission fluid.

The worst case scenario is that you have a band or solenoid in your transmission that is broken and not engaging your overdrive. Your transmission has 3 gears, and when the overdrive is engaged, it simply links 2 or more to the gears together to achieve overdrive. It would seem that something is preventing that from happening when the engine is cold, and simply making the gears spin freely as in neutral.

I would recommend finding a transmission shop to inspect this problem. It may be a simple $100 fix, or could end up costing you a couple thousand for a transmission rebuild. But get the inspection from a transmission professional before performing any repairs. And don't be afraid to get more that one opinion from more than one transmission shop.
Good luck!

the flashing overdrive light indicates a code for the transmission you need to have your codes read to see what is causing the problem