TC Electronic M-One won't boot...

Hi people... I just found this place.

I had a TC M-One on the shelf for quite some time and wanted to use it again. But...

... the unit won't boot properly . I get on-screen gibberish during normal power on.
However I CAN boot up the machine while pressing "enter" and access the "reset sys param" message and execute it but it doesn't do anything after.

I read on this forum about faulty TC PSUs but I guess it wouldn't power at all if that was the case with my unit.

Seems more like a ROM chip issue or software maybe.

Any guess? Similar stories?
Thanks!
Phil

I had same issues, after having a lot of problems with the Mone not powering up because of damaged PSU, moving the IEC at the back was making it start with all the screen symbols lighted up, and i could also acces the "reset sys param", i wasn't in DIY at that time, changing the PSU made it start nicely, from my experience tough.

From lessons learned with my DSI PER I opened it up and pushed down on all the IC's... Especially on the ones with the pins on the side and wohla she worked perfectly. I inspected the PSU and that looked ok for now.

Kaz

Yes the general consensus seems to be two possible issues with TC stuff:

1) the chips pop out of their flimsy sockets. Push them all down and see if this resolves

2) ripple and stuff on the switchmode power supply. Try and test the caps.


I am also not sure about the M one but maybe there is an internal battery in this? Check this as well.

Hope this can help you.

most likely PSU -

You can order them from anywhere that sells TC products - Sam Ash etc...Guitar center is a hassle sometimes.

Part #7E50000101

Repair it and save yourself a fortune !!
http://www.groupdiy.com/index.php?topic=20801.0

I tried pushing in the chips without any luck...
I'm comfortable with electronics so I'll try testing/changing the caps in the PSU.

I saw in the other TC thread that caps with smaller values could be the problem...

I'll keep you posted...

Thanks yall.

did you check the backup-battery? sometimes an empty lithium-cell or an old nicd-cell causes things you've described...

I know this is an old thread but for those googling via the internet. This thread helped for My m-one with same symptoms. I opened it and just pushed down all the chips and ribbon cables (They got glue on them so more then likely TC Electronics did that as a last ditch effort to keep them from falling out)
thx
quacks

cool deal...

I had not unpacked mine from a couple moves. I think the chips were just slightly unconnected and one push as we were back in business.

I have fixed a few digital reverbs in my time especially the inexpensive tc's like the m-one and inexpensive lexicons. 9 out of 10 times there is usually a fault in the PSU mostly from a blown electrolytic cap or 2 or more. Check those first. Then make sure all the cips are seated properly. IIRC the chips are soldered into place and there are no sockets but I could be mistaken.

Thread resurrect attempt.

I'm having the same problem. I can get the "reset sys etc" screen but it won't boot normal.

I thought about looking for a battery to change internally but don't see one, but I did notice my PSU looks funky, gunk around a couple of the ceramic caps and 1 elec cap. Is this what leaky caps look like ?

Reckon I should just order a new PSU or replace all the caps in the PSU?

Thanks for any help

Exact same problem here. Switching it on shows a bunch of gibberish on the screen. Turning it off keeps the LCD showing the same thing but with no backlight (???). I can also get the "reset" stuff, no problem there.

Leaving it on for about 10-15 minutes jolts it back into fully working. Nothing I do before that (turning on, off, cutting power, etc) does anything to make it work.

It does this sometimes, especially when it hasn't been used for a while or it's been transported. Something like 7/10 it switches on the way it should.

Any ideas?

Fuccimain: the gunk looks like glue. I have the same on mine, in the same positions.

Hey tgs,

Thx for that info. I just decided to order a new power supply since it wasnt expensive, and seems to have solved other people's problems.  Ill let you know if it solves the non boot issue once I get it installed and running. Should be by the end of the week.

I have seem this happen many times with various tc m-ones.

For starters they are very prone to failure due to heat. When racking them best to have 1 RU space between them and other modules.
As for the problem itself, I have been lucky that a few times it was capacitor related and one could easily see the blown electrolytics. Replace them and it was working fine after that. Use high grade high temp electrolytics as the stock ones are rated for 85 degrees and prone to heat failure.

Outside of that I have seem the rom go bad and like before is heat related, at that point we usually sent it out for repair as at the time we didn't have SMT rework tools to desolder and resolder SMT parts

The gunk is glue, It is put there to offer strain relief and over all keep things from moving about and shorting out. It's harmless but over time becomes quite hard and brown. It's a pain to remove and usually gets in the way.

The primary issue seems to be the MAIN FILTER Cap leaking AC into the circuit.

I may have found the problem with mine! This is the first time I ever try to troubleshoot capacitors, so please bear with me. Hoping to learn something from this. 

I went through the electrolytics one by one (I have a desoldering station luckily) and they measure fine mostly. One 10v 470µ cap measures 514µ, but that's still within specs, right?

I then came to C19, a 6.3V 1000µ cap. I've never seen a broken cap before but this one looks suspicious... Some brown-red gunk on top, a bit on the bottom, and the rubber pad at the bottom sticking out. Doesn't look right! I measure 638µ, which then gradually drops slowly.

I'll get a new one next week and replace and I guess then I'll know, but could this be the culprit?

Here's a picture:

So I got the new PSU pcb from full compass, I ordered the pSU for the m-one xl, and the IEC inlet is in a different location on the PCb, so it won't fit in the unit.

I've got an email into tc to try to sort this out so I'm still waiting to get this going. 

Trying to narrow things down a bit. My supplier is a bit of a drive away so I want to be sure I know what to get before going there.

I found schematics for the PSU:
http://www.dirk-hendrik.com/temp/TC_electronic_SMPS%20JKS020Q1.pdf

Now, C10 looks slightly bulged on top so I figured I should replace it. It measures fine but I guess it's best to change it anyway. It's also rated at 85 degrees while all the others are 105, so from what I read so far that might be a good idea to sort out. Any comments on that?

Next up, C19, as I mentioned before, looks really bad so I will replace that for sure! However, looking at the schematics it says 470/10, while the blown one in that position right now is 1000/6.3! So what should I go for; 470/10 or 1000/6.3? I checked the values of all other electrolytics on the board and they correspond to the schematic I found, so it's only C19 that deviates.

i have found the 85 degree caps are more prone to failure in the m-ones especially when they are in a rack with out any spaces between units for ventilation.

go with the 105 degree caps.  Secondly replace the cap in the picture.  As for c19 I would go with the value on the schematic. It's highly possible there was a mistake when they were making these. Very easy to grab the wrong part if your not paying attention.