OK, X48-ers - who's had a recent "failure to boot" issue?

Wow, was I wrong! Put the new battery in and NOTHING! Won't power up, just totally nothing at all. The unit worked perfectly and had less than a few hours on it before it was not used and dormant. Any other ideas? I can't believe anything major could be wrong since it's been sitting in a dry environment with no one messing with it. ???
DJT

Hi DJT,

I bought a second hand x48 and I realised it wouldn't boot unless plugged in for 5 to 10 minutes before hitting the power button.

I thought it was a dodgy battery, but after a replacement and a bios reset (thanks Hellvis!) the problem persists.

Perhaps if you leave it plugged in for a while it'll fire up.

Personally I'm a little confused as to why this would happen... but it might be a "feature" : (

Good luck,

Al

Hi Al and thanks for the response. My X48 was never unplugged, it just sat unused and is still plugged in. I'm puzzled since it was so little used (very, very little) and worked perfectly the last time used and no catastrophic events. Everything else plugged in to the same places fires up. I can't believe it's the power supply since nothing could have caused a problem. I'm wondering if there's a fuse somewhere? And I'm thinking maybe the power button which I never did like. But aside from that, I am totally puzzled since this should not be happening based on the use, non-use, and location of this unit. ????? I'll be reaching out to some other folks as well and already have started that process.

Thnx,
DJT

Update on my unit for everyone's info as this may be helpful. After replacing the 2032 battery and still nothing, and conversations with a local computer guy and 2 Tascam QA guys, it appears the problem is most likely the power supply. The Tascam guys indicated if the unit is unused or even plugged-in and just sitting, without it being powered up at least monthly, the cap on the power supply will drain and go bad as it needs to see periodic voltage! I've partially disassembled my unit to get to the supply, thinking I could replace it myself and the last Tascam guy walked me thru the steps but he also said he recommended to replace the power supply with one of theirs because it's uniquely wired, otherwise some other aftermarket replacement would have to be modified. He indicated they're not cheap (Tascam cost $400). So it looks like I'll be taking it in to a Tascam authorized repair shop instead of ordering the supply myself just in case for some reason it ends up not being the supply, so I don't get stuck with a very costly power supply. Also, Sweetwater, where I bought my X48/DM4800, does not do repairs on the X48 in case they're your dealer.

Many thanks to Hellvis for the "handwritten" BIOS instructions! They were invaluable! After getting my unit back with a new power supply installed, I followed the instructions and all is OK again. The X powered up and booted as before.

Just fyi and some additional info for all concerned as my problem (bad power supply) will most likely become someone else's at another time. So, as stated in the other thread I started here, it was confirmed that my power supply was bad. I had a local (Detroit area) authorized TASCAM repair facility, ABL Electronics in Madison Heights, MI do the repair for $541 total which included the new power supply they ordered from TASCAM ($371 and the rest labor, tax, peripherals, etc.)

I also did some research on power supply repair since I now have a bad but costly extra power supply that I plan on getting fixed and retaining as a spare, and am posting a very informative and educational link for those that may be interested.

As you'll see in the various videos, when caps go bad on the power supply board, they have a tell-tale appearance that their leaking; top is no longer flat, but is domed, so, it's pretty easy to tell which ones need replacing even before doing any additional testing which is done with an ERS meter. Once the bad caps are found, they just get unsoldered and the new ones re-soldered in place. As you'll also see from the link, typically the units are replaced and not repaired, but repair is not that difficult if you find someone to do it or want to take the task on yourself.

The below links have many different videos posted some of which are for power supplies found in different types of hardware, but some also for computer-type power supplies which are similar to the one in the X48.

https://video.search.yahoo.com/sear...2xvA2JmMQR2dGlkAzQxMV8x?p=power supply repair

http://www.bing.com/videos/search?q...&mid=72BF8BD5B6A3C2EA151F72BF8BD5B6A3C2EA151F

DJT

Greetings, and thanks for the excellent info. I had the dreaded dead battery on the MB and had to redo the bios. Also FYI I purchased my X48 off eBay several years ago in a non functioning condition due to bad power supply. I refused to buy the hi $$$ Tascam version and found a fairly standard and quieter higher wattage PC power supply that worked just fine after some slight mods to the case (the power supply had an on/off switch). Also added 1T HD at the same time and until the recent dead battery had been working flawlessly. Cheers

Hello MBI; thanks for the note. The reason I didn't try to go with a commercial, non-Tascam branded, off-the-shelf power supply was based on what the Tascam guys told me. They said an off-the-shelf unit wouldn't work without modification (of some unknown nature and they didn't tell me what specifically the differences would be) and suggested I use their unit, which advice I believed and did. When you look at the power supply in the X48 it looks like a normal computer type, but nevertheless I bit the bullet and bought theirs as part of the repair at the local Tascam authorized repair shop. I'm in process of getting my old one repaired which I'll probably sell. I was going to do the repair myself since it looked pretty easy after doing some research and watching the U-Tube how-to videos, and popped the cover on the it. I could see 2 bad caps which were easy to get at, but a third bad cap was nestled next to a heat sink and much harder to get at and you couldn't tell where to unsolder on the back of the board because of it's location, so, the old PS is out being repaired.
DJT

Thanks to everyone here for the info. Brought mine back to life with the bios settings.

Thanks, Paul for bringing up this issue once again. I've subsequently discovered (since my first successful battery/bios re-boot) that I've apparently got the dreaded defective power supply. HOWEVER, when chatting with our Mr. Farrell and his tech, they both insisted I replace the motherboard (to the tune of $600) - something I have not yet done!

I surely know the difference between a motherboard and a power supply; yes David R. indicated the problem was capacitors failing, but it seems I was misdirected as to which. Other than an on/off switch, which standard hi/wattage supply has been shown to work in the X48? I, too would like to increase the disc size when doing this repair. Need a part reference, please?
HellvisPresley

Just fyi again to all that may be interested, I do have a spare TASCAM power supply that I can sell a whole lot cheaper than buying it from TASCAM since when I had the power supply problem, the local TASCAM repair shop did in fact get me a new TASCAM power supply from them for the above mentioned very high price, and after I got my X48 back, I had the old one repaired; it had 4 bad caps. As stated before, I would have tried the repair myself but a couple of the caps were in very precarious places which started to become a bit too difficult for my taste so I had it repaired by another TASCAM local shop that was more capable than I. So if anyone is interested in my repaired TASCAM power supply it's available.

I am not sure what caused my X48 to loose its mind. It was working fine. I cycled the power and it didn't boot. I thought it was the hard drive so started down that route to replace it. Then I noticed it wouldn't even boot from the CD. So I ended up here and the BIOS settings fixed it.
While I had it opened I changed out the battery.
I also replaced the hard drive with a WD Blue ( WD5000AAKX) 500GB drive that I had handy and so far it has been working fine and booting with a full load of input cards, drives, etc. The original drive did boot too but was noisy.
I plan to put a meter on the PS and see if there are any signs of trouble.
I no longer have complete confidence in this machine and have booked JoeCo Black Box as an inline back up for my next remote recording session.

So here's a wrinkle. Changed out the battery in one of my X48s, reset the BIOS and it booted up perfectly, but now it won't recognize or mount a drive on the FW bus. Anyone else see this? Suggestions?

Got it figured out. When resetting the BIOS, in the IWILL SMART area, make you sure you check the 1394 option to ENABLED. It comes up DISABLED and wasn't documented. I'm not complaining!

Thanks for your great info about BIOS settings. My X48 worked just fine, a few months without powering up, then no signs of life. No booting at all. Took off motherboard to a local repair tech, he replied to get motherboard's chipset dead. So , if anyone can help, about motherboard repairing or replacing, not to spend $500 at a glance. Thank you all!

Two X-48's with problems... I need to stay away from digital and remain analog...

help!!! this is the classic bios error?I can fix it with the info here?

Greetings, all:
Sorry to have been away for a while. Yes, the first line of failure on X48's is usually the backup battery. Changing it leads to bios needing reset. Awfully sorry about missing the IE1394 config on my original post - that came from Tascam tech support.

However.....it seems there's a plethora of other possible issues, not the least of which is the above described power supply and motherboard failures. Giving all due credit sight unseen to the techs that made those diagnosis', what I've recently experienced merits disclosure.

After sitting a while again, the X48 wouldn't boot. Taking to my tech this time (knowing battery was fresh), we suspected a power supply issue, as others had experienced. A Tascam p/s isn't needed - generic versions work fine. However, replacement (and testing of old p/s) did not resolve issue. Tech concluded after testing drive, basically taking unit entirely apart (thanks to my Nordic buddy who supplied a Service Manual!) that the bios had become corrupted. Re-setting it yielded a good boot once again. Several more weeks of performance went by, until I started to experience cursor freezes, and playback discontinuities. Then - BSOD! My unit continued to deliver BSOD (blue screen of death) until no boot at all....

This time, it was catastrophic hard drive failure. Now, with a 7200rpm "black" label 320gb drive, we're cooking again. Note - no power supply or motherboard issues of ANY kind! Think simple, folks - don't let the tech snowball roll. Also, after deciding to go full
AES with my I/O cards, I read of a firmware update for the MKII version machine which fixes a problem with those cards. Running the duly authorized v2.02 already - I dared to install the v2.03 from the MKII column. Works just fine!

Feel free to keep this thread living, as we need to document the various causes of "failures to launch".

Thanks, and Aloha -
HellvisP.

I have a chance to score it one for $430 (for repairing) is worthy?

Well - that all depends....if it's just a frustrated X-48er bailing for lack of patience on a simple reconfig/repair, then yes. That price is about ten cents on a dollar to what I spent new.

However, if said X-48er tossed the unit from the 8th floor of the Brill Building in NYC out of frustration......
Cheerio!
HP

Just wanted to thank Hellvis for the PDF, it saved my cookies.

Aloha, all:

Here's a tiny update.....wanted to verify my ie1394 firewire performance last night, so I hooked up an external drive, which worked fine, both for project transfer and real time playback. This is notable since I haven't changed the BIOS config since doing the reset as at the start of this thread. The FW setting is "on"; the other fellow who thought it missing must have overlooked that toggle. Of further interest: I'm now running v2.03, which is released only for X48MKII's. My MKI's are running fine with this - INCLUDING ie1394, in spite of the newer hardware replacing it with an eSATA port. This is the most recent (possibly last?) revision to the OS code, which allegedly fixes problems with the AES card implementation.

In summary: a) the BIOS which I've posted is complete and accurate.
b) use of v2.03 is HIGHLY recommended, as it represents TASCAM's final
word on bug fixes for both units.

Thankyouverymuch!

HellvisP.