On my apple ipad mini model A1432 that I bought from a friend the passcode that I'm putting in is incorrect. How can I get a new passcode?

You probably know this as you are able to replace a motherboard. The question is confusing. It sounds to me as though your saying your display light either stays on or comes on randomly, this is either a fault in the wiring or the soldering. You will probably have to go back inside the pad.

The following can be done on ipad with iOS 8:
1. Press the home button( the round button on the front side of your ipad), to go to the home screen.
2. Find the Settings icon ( looks like gray clockwork gears) and tap on it to launch the Settings app.
3. After settings app is started try to find on the left side of the screen Passcode ( has a red lock icon near the text) and tap on it
4. In the passcode setting screen you can choose the type of passcode with the Simple passcode setting switched on or off ( simple means a 4 digit number, not simple means any character combination
5. By taping on Turn passcode on you can enter your passcode. Be carefull not to forget your passcode, otherwise you will not be able to use your ipad later.

The quickest and easiest way would be to take it back to the store you purchased it from, and ask for some guidance. They must be pretty poor to have sent you home without showing you even the most basic processes relating to your iPad.

If they are unwilling or unable to help you, take it to your nearest Apple store. I'm pretty sure that even if you didn't purchase it from them, they'd most likely be prepared to give you a few minutes of their time to introduce you to the machine and how to get it going :o)

There is really no option except to erase the iPad with iTunes. It is a security feature that is built into the iPad operating system. You can follow this guide, although it says it is for iPhone, it applies to iPad too!

http://support.apple.com/kb/HT1212

The best way to figure it out is to hold the Ipad mini against the light and see if you can tell what his unlock pattern is. If his screen is clean you wont be able to tell.

After you put in the wrong pass code 3 times, you only can unlock the iPad with the correct password, belonging to the Apple ID from what is only a part shown on the screen. If you don't have the passcode nor the password Apple assumes you are not the legal owner, and you can't use the iPad anymore. Just go back to your friend, ask him to unlock the screen, to wipe the content and reset the iPad to factory settings.
For that goto settings, general and scroll to the bottom line and press that. then the second line wipe everything. Again the login code is asked. but after that the iPad is empty.Your friend should also remove the iPad from his list of registered Apple equipment.

It's usual for us to forget the passcode, however, there are several ways to reset the iPad password. Just follow one of them shown below.

If you've neither synced with iTunes nor set up Find My iPhone in iCloud, you'll need to wipe your iPad to factory setting to remove the password, which means you'll suffer losing all your data on iPad and get it as a new one.
Please pay attention there is a slight difference in putting different models of iPad into recovery mode.
iPad Air

• 1. Turn off your iPad Air, press and hold the Home button.
• 2. While holding the Home key, connect the USB cable to the device. Wait until the Apple logo appears and keep holding the Home button for few more seconds.
• 3. Continue holding the Home button until the iTunes logo appears.

iPad mini/iPad pro

• 1. Connect your iPad to your computer or laptop and open iTunes.
• 2. While your device is connected, force to restart it.
• 3. Press and hold the Sleep/Wake and Home buttons at the same time. Don't release when you see the Apple logo. Keep holding both buttons until you see the recovery mode screen.

Now you have entered the recovery mode, and

1. When you see the option to Restore and Update, click it.

2. Wait for the process to finish. Then you can set up and use your device.

For more methods, check: How to Unlock iPad?

Plug it into your computer and select factory reset on it in iTunes.

I activated my voice over, and now its lock. I cant even put my passcode on it. please help..