It just said enter the unlock code because the battery died

It's either in the owner's manual or the dealer will have to give it to you. Get the VIN from the car (registration?) when you call them.

GL,
Td

connect a battery charger to it while the key is on

Hi,

Thank you for contacting fixya.com.

The key lock/unlock for doors are powered by the batteries in the remote, while the ignition key draws its energy from the vehicle via induction. Since the battery is dead you are having this problem. You need to call assistance from the nearby auto shop or a locksmith. I guess you don't have any other option.

Use the radio preset buttons to enter the unlock code.

my sources tell me that if you entered the wrong code three time the radio will lock up and will require dealer assistance to unlock, theft feature

If it is the correct code, you may have entered it a few times & locked the system. Either disconnect the battery & wait a minute & reconnect & retry, or pull the radio fuse & retry after waiting a minute & reinstalling.

contact your local dealer, you will need to remove the radio to be able to read the serial number off of the top.

This is the anti-theft device on your factory radio. When the battery died, the radio thought it had been removed from your car and went into anti-theft mode. When you turned the car back on, the radio should have read "CODE" on the display, at which point you need to enter the factory anti-theft code. After 3 failed attempts at entering the code, it will simply read "OFF" and the radio is locked.

At this point:
- find your factory anti-theft code - it should be in your owner's manual, or you can contact a dealer to retrieve it
- turn the key to the ACC position (radio and accessories on, but engine is off)
- turn on the radio so the display reads "OFF"
- let the car sit for 1 hour
- radio will turn off automatically and reset
- turn the radio on again, and it should read "CODE"
- enter the factory anti-theft code

Make sure you have the code before starting the procedure. To enter the code, use the radio preset buttons. For example, if your code is "4321", hit Preset #1 button four times, Preset #2 three times, Preset #3 two times, and Preset #4 one time. Then hit the "Tape" or "CD" button. Radio should now be unlocked.

take it to an acura dealer and they can unlock the radio for you if you don't have the code.

I've had this happen twice when the battery died. It goes into the SAFE 2 mode if you try entering it and don't do it right and then you have to leave the radio on for 1 1/2 hours to have it come on to 1000 and then set it with each number one at a time and then hold down right reset until he beeps on. So, if you are discouraged as I was, the answer is to leave it on with the SAFE showing for over an hour and it probably will come on with the 1000 for setting eventually.