I recently disconnected my battery and now I don’t know how to turn my stereo on Before I never could turn it off Can u please help me learn how to turn it on?

MAKE SURE THAT U CONNECT ONLY THE WIRES NEEDED FOR THE UNIT TO OPERATE.CHECK ALSO AT THE CARS WIRING IF THERE IS AN EXTRA BROWN WIRE OUT OF THE WIRING FOR THE RADIO.LET ME KNOW.ALSO IF THE AFTER MARKET RADIO HAS A DETACHABLE FRONT FACE.

Unfortunately in newer vehicles, they sometimes need to have the computer re-flashed IF you unhook the battery with the radio on. It's a crummy deal. The dealership will probably have to re-flash the computer. You could try turning the stereo off, then disconnect the cables on the battery for a minute, then re-connect and POSSIBLY it could reset the system and it may work again. Don't get your hopes up, this may not fix it.

You can try to disconnect your battery for about 5 minutes and that will usually reset the computer.

Most modern OEM stereos require coding changed to accept an ipod. Dealers can do this so can decent garages. To reset the unit try disconnecting and reconnect the battery but be prepared to lose learnt data, this means the car may require a re-learn / drive cycle afterwards

you need to contact the manufacturer of the vehicle and tell them the vin number and they can give you the code ( you could pay a fee for this info ) this solution only works if the stereo is an original fitment to this vehicle.

Have you had the battery disconnected recently? The stereo on GM cars have a security feature that locks them down if the power supply is interrupted. You would have to contact your dealership to get the code to reactivate the stereo. If there has been no disruption in the power supply, then check for blown fuses.

If your battery goes flat or you disconnected the car battery, your car stereo anti-theft security system will be activated: you need to consult your car/radio user manual to remove this lock and will need the correct security code.
Hope it helps: please let me know how you go!

go back to whoever serviced it and get them to sort it out if they have caused the problem

1st thing to check is the battery. The clicking sound you hear is a common sign of a dead battery. Have u tried to jump start the car, or charge the battery? Check this 1st, let me know what u find, then we can take it from there.

try disconnecting the battery for several minutes then reconnect this may act as a reset and bring the stereo back to its original state