Thunderbolt stuck in "turn on" loop

[mdr]

My Thunderbolt won't turn on.  (Got this phone June 2011.)  When I press and hold the power button, the white "HTC" screen comes up. After 11 seconds it vibrates once.  5 seconds later the screen goes dark.  5 seconds after that the white "HTC" screen reappears and the same loop occurs.  It never gets to the "Thunderbolt" screen.  The only way to make the loop stop is to remove the battery.  After replacing the battery, I try to turn it on and the same thing happens.

I have two batteries.  Neither solves the problem, so I don't think it's a battery issue.  Going through all this with the charger plugged in makes no difference.  Have tried leaving the battery out a couple of hours -- no difference.

Anyone have any ideas?

[BakerGeckos]

You can try a wipe the device by going into the bootloader by holding vol down while powering (I usually Pull battery and do this) on the Device. this should take you into the bootloader and you can use the volume key and select factory reset and press the power button. You can clear cache levels in revocery but thats more advanced....this should get you going again...

Mike

[mdr]

Thanks for the reply, Mike.  This is really new territory for me.  I didn't even know this existed.

I got into the "bootholder(?)" screen.  (It says "HBOOT" at the top, with a menu of options that I can scroll through below.)  I tried "FASTBOOT" which provided a new menu with other options.  I tried those, and they had no effect.  I went back to the "HBOOT" screen and tried "RECOVERY", which put it in the same power-on loop I was in before.

I haven't tried the "FACTORY RESET" yet because I'm concerned about losing data.  Is there any way to know what I might lose?  I don't know, really, how the SimCard and MicroSD card work.  I have my contacts on Back-up Assistant, so that wouldn't be a big deal, but I'd rather not have to reinstall apps and recreate calendars and everything.

[mdr]

Update:  I tried "FACTORY RESET" and it just put me in the same loop I was in before.

[BakerGeckos]

it shouldn't wipe the SD card or mess with the sim card, It does remove everything off the device. if you have backup assistance your contacts and backed up there and in most cases if they are on the google account they will be restored after the reset. If you have google + on the phone your photos are stored there. If you want you can remove the SD card before you do the wipe but it should be fine leaving it in.  You can try recovery mode but I am not 100% possitive in the commands or key sequences in that mode and don't want to steer you wrong there...

Good Luck

Mike

[BakerGeckos]

I'd call Verizon and maybe they will walk you through that process to format the cache or you can search the internet for a Factory RUU which can restore your device to factory Current version of OS is 2.11.605.9 Should be able to use that to restore your phone.

[mdr]

I tried everything I could from the "HBOOT" menu.  Nothing worked.  I called Verizon support.  They were mystified.  I took the phone to a Verizon corporate store and a guy there spent 20 minutes trying to get it working, but no luck.  I had to order a replacement phone.

Thanks, again, for your help!