Now that yalu102 has been out a while, along with its unstable predecessor for iOS 10.0-10.1.1, many of our readers will no doubt be running one of these two jailbreaks. As is always the case with a jailbreak on a new iOS version, many tweaks are not yet updated, and some can cause crashes or even bootloops.

It is consequently useful to be able to get into No Substrate Mode, to be able to escape tweak-related crashes and remove offending tweaks. The process has changed slightly since the days of the untethered jailbreak due to the fact that current semi-untethered tools do not boot into a jailbroken state. In this guide, we’ll show you how No Substrate Mode is accessed on the Yalu jailbreaks.

What is No Substrate Mode?

Firstly, to clear up any confusion, let’s go over what No Substrate Mode is. It’s a mode which is cleverly built into Cydia’s functionality allowing you to enter a jailbroken state, but without Cydia Substrate running.

At first sight, it may look like an unjailbroken state, because most tweaks rely on Substrate to run, and with it disabled they will have no effect. Modifications to the status bar, icons, badges, etc, will all disappear as if the phone was back to stock. However, the phone is in fact in a jailbroken state, and Cydia can be opened and used. This allows you to use Cydia to remove tweaks which are causing your device problems, which you could not remove with Substrate enabled due to the tweak crashing your phone constantly. It is therefore a powerful safeguarding and troubleshooting mechanism for your jailbreak.

No Substrate Mode is not to be confused with Safe Mode, which is a different state. You may have encountered Safe Mode before, if a tweak crashes your Springboard. The phone will respring, and your wallpaper will be black. A dialogue will appear informing you that you are in Safe Mode, and offering to restart back into normal mode. It will also say Exit Safe Mode in the status bar of your device. In Safe Mode, Substrate is running, but all tweaks are disabled. Safe Mode is not normally entered on purpose, but happens automatically when Springboard crashes. By contrast, booting to No Substrate Mode is deliberate, and disables Substrate entirely.

Entering No Substrate Mode on jailbroken iOS 10

1) If you are already in a jailbroken state, reboot your phone to an unjailbroken state.

2) Launch the Yalu jailbreak application, and locate the Go button.

3) Press the Go button to begin the jailbreak process, and then immediately hold down the Volume Up and Power buttons.

This combination is the same for all devices. On some devices the Power button – also known as the Sleep/Wake or Lock button – is on the top of the device, on others it is on the opposite side to the Volume buttons.

4) Keep holding down Volume Up and Power/Lock buttons throughout the Yalu app’s jailbreaking process, and whilst the phone resprings.

5) Once the device is back to the lock screen, release the buttons and unlock the device.

6) Check that the phone has not rebooted to an unjailbroken state by trying to open Cydia. If Cydia opens, you are in a jailbroken state.

7) Check that the phone is in No Substrate Mode and not normal jailbroken mode by looking for the effects of any of your tweaks. I normally check my status bar to see if my carrier name is gone and my wifi bars have become dots, because these are two instantly visible tweaks I have. You can check for whatever tweaks you like.

  • If Cydia opens and your tweaks are working, you are not in No Substrate Mode, you are in normal jailbreak mode.
  • If Cydia does not open, you are in an unjailbroken state.
  • If Cydia opens and your tweaks have no effect, you are in No Substrate Mode.

8) Use No Substrate Mode as you please, to remove conflicting or incompatible tweaks.

9) Once you are done, exit No Substrate Mode by simply rebooting your phone. You will have to re-jailbreak with the Yalu app after the reboot.

No Substrate Mode can save you from all kinds of sticky situations. In fact, there are very few problems which it cannot help to fix in one way or another, due to the fact that most jailbreak problems are tweak related, and most tweaks are Substrate-dependent.

With Substrate disabled it is normally possible to troubleshoot, fix filesystem problems, and remove dangerous tweaks, without having to restore the troublesome device. Of course, there can be more serious problems with your jailbreak which are not due to something which relies on Substrate, in which case this will not help you, but in my experience these are the minority of cases.

Has No Substrate Mode ever saved your skin? Did you know the difference between Safe Mode and No Substrate Mode? Did you think No Substrate Mode had died with the untethered jailbreak? Let me know in the comments.

  • Jeiivy

    I Downloaded a tweak “app sync” by mistake messed up my jailbreak, had no choose to upgrade to lasted iOS. I did everything to get it working with no luck.

    • David Gow

      Man that sucks

    • Andres Torres

      Yeah, it’s recommended you don’t install Appsync, because it causes a bootloop.

      • Jeiivy

        it hide all my stock apps couldn’t do nothing

    • Joaquim Barbosa

      Could you get into No Substrate Mode to remove it? Or did you not try?

      • you could have also used iFunbox. Its weven better than subsctrate mode.

      • Karloz25

        How do you use ifunbox to recover from bootloop????

      • you can remove the bad tweak

      • Karloz25

        ….

      • Jeiivy

        I did everything Lydia was no where to be found, no setting apps no safari nothing, I even did the volume up to enter safe mode and nothing.

      • harman

        I ran into the same problem and all I had to do was simply rejailbreak with impactor

      • Jeiivy

        How you do that?

      • Joaquim Barbosa

        Look at my recent article which shows you how to enter No Substrate Mode.

  • droid3000

    you dont have to hold the power button btw, iv had my fare share of run ins with substrate the past couple of days

    • Joaquim Barbosa

      Hmmm. I tried it without because someone also said that, but it didn’t work. How strange. What device?

      • droid3000

        im using a 6

  • id like to jailbreak my 6s 10.1.1 BUT i want atleast a stable jailbreak kinda like 9.3.3 ios jailbreak, but right now theres too much ppl getting upset with the tweaks havent upgrade it yet, so i’ll wait a lil bit longer.

    • Blacklight: Retribution

      Today my new iPhone SE came to me and it was on iOS 9.3.3 but at least I was able to jailbreak it easily.

      • Lucky you ☺️

  • andrei endriu

    Should I stay wait on 10.1.1 i7 ?

    • Joaquim Barbosa

      Stay, for sure.

      • andrei endriu

        Ok thanks .

  • bushygoodness

    If ios 11 isn’t more configurable, I’m switching to the Note 8 – pending it doesn’t blow up. I’m tired of waiting for stable JB’s.

    • i was thinking of changing to a S7 cuz its more customizable, BUT i like tweaks and thats something android doesnt have.

      AND my saved games are on game center, i could not play my saved games on android, thats another reason why i wont switch

  • Diego Mejia Gonzalez

    Should I stay wait on 10.1.1 i6s ?

    • Joaquim Barbosa

      Yes

  • ravinigga

    Maybe problem is I’m jail broken state tweaks works but Cydia won’t open anymore even reboot that stuff problem Cydia crash

  • SohrabR

    Still on 10.1.1 iPhone 7 plus waiting on stable release

  • William

    Do not install this app from Cydia it is frozen and I can’t even boot into safe mode
    Dragmedown for iOS 10

    Any help would be appreciated.

    https://uploads.disquscdn.com/images/97b2710547a71f318ab086d6a71a9751a3d7a109552356cfd2e86815e8409455.png Do not install

  • milagros arrascue

    I wanted install cydia 10.2.1 but I couldn’t because I show this: enter your number to unlock this content .
    There are no error Plays for download
    Please!! I need help