My nissan frontier blows the automatic transmission fuse when attempting to start and it will not go into overdrive

On overdrive not working = check the 'Revolution Sensor' (on transmission output area, check the 'OD' Switch.

On the fans - fuse panel under hood - two relays one for the 'thermostatic fan' the other for the A/C fan.

This is a duplicate question.
You are saying the overdrive button does not affect the transmission.
What was the trouble code stored in the computer ?
Chances are it is a problem inside the transmission.

An expert at a shop ought to look at this---could be a shift module or electronic or mechanical problem.

It might also be a sign something bad is about to happen.

Electronic or mechanical issue?

If it's an automatic, You see the Following: P R N D 2 1 etc. Some may show: P R N D 3 2 1 or .... 3 2 L ... D 2 L etc.

To really determine whether it's a 4,5 or 6, take into consideration if it has Overdrive.

Count however many gears are on the column, as listed above, plus overdrive. this will give you your answer.

Ex: With Overdrive: P R N D 3 2 would be a 3 speed ( 2 3 D) with overdrive.

Check the fluid level of the transmission. Also if you haven't done so in the last 30k miles change the transmission filter/fluid and pan gasket.

From Nissan Frontier Owners Manual:
For Automatic Transmission Fluid, refill with Nissan Matic D

More details HERE

Hope helped (remember rated this help). Good luck.

check for short circuit

check if linkage is touching bare wires

juan: there is a cable which comes from the transmission to the throttle linkage. This is called the TV (throttle valve) cable. This is designed to work in conjunction with the position of the throttle. I'm sure you heard the term "KICK DOWN SWITCH". Well this essentially is doing the same thing. If the cable is out of adjustment, it will have a tendency to want to downshift into 3rd.
Even though overdrive is electrically actuated, it can be disengaged by the throttle position.
There is also a coolant temp sensor which keeps the transmission from shifting into overdrive until the coolant temperature reaches a certain point. The sensor tells the ECM to tell the Solenoid it's ok to supply a ground to it.
Your overdrive switch provides a ground to actuate the overdrive solenoid. Make sure the switch has a solid ground serving the circuit.
The torque converter solenoid picks up it's ground from the ECM.
Both solenoids are served by the same power source which is a switched circuit through the ignition.
I hope I have shed some new light on your problem and given you some new direction in which to look. I hope I have helped you resolve your problem. If not, I'll be watching and will be ready to offer more help if needed. ..mybunkey

actually there is a switch, if it is automatic it might be on the side of the transmission, or if you have a manual transmission then it is some where in the transmission, the diference is the automatic will be any where from the sterring or center console deopending where is the shifter