Root [CDMA] Downgrade Hboot and flashing rom

[musicfan266]

I know this may be a stupid noob question, but I will ask it anyway and maybe it will help others later. I have looked all over the forums and other to try and find the answer but had no luck finding a clear answer. So here is the question:

What are the proper steps to flashing a rom that doesn't work with the current hboot on the device?

I know the phone must be s-off and you would have to wipe everything. The stuff you have to do for all flashes, and you would have to flash the correct hboot for that rom. But what order does it need to be done in?

Flash the PG86IMG file in the bootloader before installing the rom?
or
Install the rom then boot into the bootloader and flash the PG86IMG file?
or
Does it matter which order it is done in?

If this information could keep others and myself from really screwing up their devices, it would greatly help. Thank you in advance for you time and answers.

 

[Brian706]

I actually cover this in my thread with hboot downloads. I'll copy/paste my instructions. When changing hboots to a rom that isn't compatible, order of operations does matter. Take note of the end of the quote. That's the part that gives the special instructions for changing hboots on an incompatible rom.

If you do mess up, don't panic. This scenario is 100% recoverable if something goes wrong but I typed these instructions specifically for this scenario so that you can avoid any complications.

How to use a PG86IMG.zip file!First let me start by stressing something important! Verify the integrity of the download by checking the file against its md5 checksum that I provided for each file. You can use a free software such as MD5 Checker to do the job. Or if you'd like to check on your phone without a pc, download MD5 Checker for android from the play store. If for whatever reason your download gets corrupted, using a corrupted file can brick your phone! So use an md5 checker to verify the integrity of the file, it's quick and easy and can keep your phone safe!

1. Download File. Check md5 for a match

2. Place the file on the root of your sd card (not in any folders).

3. Rename the file to PG86IMG.zip

4. Reboot into bootloader.

5. When asked to update, say yes by hitting volume up.

6. When it's all finished, hit power button to reboot.

7. *Important! After booting up, immediately rename or delete the file.

*The presence of the file on your sd card will prevent you from entering recovery in an emergency situation. It's nothing to panic about, but if you get caught in a bootloop, you will have to manually remove the file using a pc and card reader or another phone. That said, to avoid bootloops and being stuck with no way to boot up and no way to enter recovery, plan ahead. If you are on a rom that requires hboot 1.58 and you flash hboot 1.5, you will hit a bootloop and not be able to access recovery. You would then need to remove the file or flash a compatible rom through fastboot connected to a pc.

Okay. Now with instructions and warnings out of the way, I will give you my personal preference on how to flash a different hboot that will be incompatible with your current rom without getting a bootloop and having to use a pc to fix the situation.

Follow steps 1-3 above. Stop! Now, instead of rebooting into the bootloader, we are going to bypass the bootloader by rebooting directly into recovery. Some roms have this feature built in. I recommend downloading something like ROM TOOLBOX from the play store. It's a great app to have if you are rooted. Rom Toolbox has a built in rebooter menu (with widgets) that allows this function. Alternatively go get QUICK BOOT from the play store. So once in recovery, wipe and flash the rom normally. Once finished, continue to steps 4-7.

This will allow you to do everything completely from your phone and avoid getting stuck. Remember, this is just for when you are changing hboots that will be incompatible with the rom you are already using (ie: ICS to GB). Just following steps 1-7 normally is fine for just flashing radios or switching between different GB hboots etc.

 

[musicfan266]

Thank you Brian706. Please let me go through the steps real quick to make sure I have understood the proper order. Please correct me if I mess understood at any point.

1. Download the hboot and check Md5sum.
2. Put it on the root of sd card.
3. Rename the file PG86IMG.ZIP.
4. Boot into recovery.
5. Wipe cache, dalvak, etc.
6. Flash New Rom.
7. Reboot into bootloader.
8. Press volume up to say yes to update.
9. Reboot phone.

I hope I have the step correct. Thanks again

 

[Brian706]

Yep, you got it. Should be good to go!

 

[musicfan266]

Thanks again! Sorry for the noob question but wanted to make sure I got it right

 

[scotty85]

Better to ask now,rather than later wen your stuck on a splash screen. Absolutely nothing wrong at all with asking all.the questions you need to in order to have your ducks in a row

 

[xevious]

Thanks a lot for this posting, Brian. Can you link the original thread where you'd posted this?

Also, in your opinion what is the best bootloader to have installed? Are there any significant differences to make one preferable over another? From what I understand, you need to upgrade to 1.58 in order to use the Juopunut Bear wire trick for S-OFF. But once you've got that done, is it sensible to downgrade to something like 1.50 in order to be compatible with more ROM's? I assume once S-OFF, you can flash a different hboot without losing S-OFF, correct?

 

[musicfan266]

From what I understand, once you are s-off you can flash any kernel or hboot you need. The hboot you need to flash will be determined by the kernel and Rom you are flashing to the phone. Some ROM's require 1.5, some require 1.4, and the list goes on. I think there are nearly 10 to 15 different hboots. You may find more roms made for hboot 1.4 or 1.5.

Please don't take my word for it though. I am fairly new at this and my not be exactly right t out a part of what I said, or anything that I said..lol..

 

[scotty85]

. I think there are nearly 10 to 15 different hboots..

well,not quite that many

generally you will need either 1.4 or 1.58. 1.5 would prolly boot roms requiring 1.4 since it is still GB,but im not 100% sure on that.

in a nutshell roms based on stockish sense need the newer hboot and AOSP roms generally require the older

brian or DS will know better than i would what roms want wich hboots with this device