Help/Support iPhone doesn't boot past the Apple logo, then turns off

[DoppleGangeriosGods 0 iPhone 6s Plus]

While texting in messenger and imessenger my device would get a kbd crash (keyboard crash?). I tried to find the culprit, so I began by turning off everything listed as BytaFont3 in the Cydia Substrate using iCleaner Pro. The phone immediately rebooted then went into Safe Mode.

Mistakes were made: I got distracted and instead of removing all tweaks that might be causing the Safe Mode, I instead tried to jailbreak my device. Yalu wouldn't open, so I uninstalled it and attempted to side-load it using Cydia Impactor. For some reason when I tried to install Yalu, Cydia Impactor gave a Locked_Error. I then decided to [edit] force restart and the device did not boot back into Safe Mode.

The problem: Now when I power up the device, it reaches the Apple logo for about 60 seconds then turns itself off. 

Details about device: iPhone 6s+, Yalu iOS 10.1.1

Questions:

• 1) Without the Yalu app installed, is it still possible to get into Safe Mode?
• 2) Is there a way to save my Jailbreak?
• 3) If I can't save my jailbreak, is there a way to save my data?

Updated September 18, 2017 by DoppleGangeriosGods

[Rook 545.5k iPad Pro (2nd gen) 17.4 Donor]

Have you tried going into Safe Mode but holding the buttons that work with your device?

And does iFunBox recognize your phone when you're in the Apple logo?

[DoppleGangeriosGods 0 iPhone 6s Plus]

1 hour ago, DiDA said:

Have you tried going into Safe Mode but holding the buttons that work with your device?

And does iFunBox recognize your phone when you're in the Apple logo?

I found instructions to manually boot into Safe Mode for the iPhone 6 which I assume would work the same way for the iPhone 6s+. I powered up the device and then held down the Vol + button, but the device turns off while it's still on the Apple logo.

During the 60 seconds the device is on the Apple logo, iFunBox doesn't recognize it.

I went into DFU mode, and iTunes recognizes my device, but iFunBox still doesn't.

Updated September 18, 2017 by DoppleGangeriosGods

[Fadexz 5.7k iPhone X 14.3]

Maybe you turned off some of the red toggles which are stuff used for the jailbreak to run.

Can you start it normally without jailbreaking?