[LG V30 Guides, News, & Discussion] zacox123:
This thread is for those who have troubles but have no idea what to try. If you're new in playing with Android Roms, you'd better read this. No exact operation would be introduced here, because only directions are provided and further work should be searched by yourself as I'm not Mr. Knowall.

Here, trouble means problems except the cases you can boot to system (they're issues) or hardware damage. Make sure your phone has been charged or any battery related problem is considered to hardware side.

Besides, if you are holding a T-Mobile H932, you should be extremely careful with anything below, because any mistake may push your phone into hell. Especially, there is currently no usable 9008 firehose file for it even you ask a professional repairman.

First, backup everything important regularly to a secure place instead of phone storage, especially private files and EFS partition which contains IMEI, MEID, etc. If possible, write down the IMEI, MEID, S/N, WiFi MAC address, Bluetooth MAC address of your phone for potential future need of restoration.

Then I assume you have unlocked bootloader. If not, go to (WTF...!) LG V30/V30+/V30S Bootloader Unlock & Root Method (With Clear Instructions) when you can still boot to system. If you cannot boot to system already with bootloader locked and cannot perform unlocking introduced there, maybe you can jump to the section of download mode or 9008 mode and give it a trial, BUT I CANNOT ensure your phone would return normal.

There are four important modes related to our topic: Recovery, Fastboot, Download and Qualcomm 9008 (Preload for MTK). Risky and inconvenience is increasing in order. Read this: Collection of mode entries with hardware key combination (maybe for most LG models) to learn how to enter them without booting to system.

Recovery is stored in the partition with the same name. You need custom builds like TWRP or OrangeFOX to flash in, or you only have a stock one with the single function of master reset. For most cases, if you can enter all the four modes, use this first. Make a backup before flashing anything with Rec, and if the thing you flashed in leads to bootloop or anything abnormal, you can easily get the original partitions back. But if you performed incorrect operations and such a restoration doesn't work, you should consider wipe cache, dalvik cache and data (backup if not yet). If not work still, try to flash in fresh rom packages. If not work again, go to the section of download mode.

Fastboot is mainly used to flash in some partitions like recovery, boot and unlock. There is some limitations that many partitions cannot be flashed in here. If you have never used this mode before, you may need to manually update the corresponding driver on your computer (caution that if you're facing the problem of "waiting for device", it's usually driver issue). Some firmwares miss this function, so it's often recommended to switch firmware for custom rec installing.

Download mode is mostly used to deal with kdz files. You need LG phone driver and dev patched LGUP (or some other tools with similar functions). If LGUP cannot recognize a phone already in download mode, it's usually the problem of driver or LGUP patcher. Be careful when using LGUP. If any interrupt during the process of downloading firmware, you need go to 9008 mode. Do not use chiperase unless you know what to do after that. Here again dump can backup partitions. Refurbish and partition dl are most widely used. This mode can solve most troubles unless you cannot enter here. If that really happens, move on to the ultimate mode, 9008.

9008 is the last chance before sending your phone to repair. Only recommend to recover other modes, but if you're familiar with it, you can do almost everything in this mode as in other modes. Again driver and tool are needed. Recommend QPST since it's made by Qualcomm, but it's not released publicly. Search and download from some reliable sources. The driver needed should be contained in the package with the tool. Somebody may tell to use QFIL, but if you have not installed it please install QPST and use the built-in QFIL instead of a standalone one, or problems would probably find you. To use this mode, you need the corresponding firehose file. See this: LG V30 Unbrick guide (Qualcomm EDL 9008 Mode, Hardbirck, with no download mode) for file download (none for H932 yet). You do not need XML file if the partition table is not broken. To verify it, open QFIL built in QPST, set configuration to UFS mode, open Tools -> Partition Manage and see if it's correctly displayed. If yes, only flash in partitions related to bootloader and recovery to get other modes back. The partitions can be found in twrp flashable stock firmware or early backups, or you can extract from kdz using LG firmware extractor. Only the worst damage to storage needs full download with XML generated from kdz using extracting tools.

If all modes above cannot save your phone, you may consider hardware damage and that needs professional knowledge, so our forum cannot help.

Good luck.