Revive a TIU

I have an old TIU, the original G model.  We've used it for some time on the club layout.  However, it isn't responding at all to the remote, and I can't find it on any of the TIU numbers.

When checking the flashing light, it flashes either 9 or 10 times!  Clearly, that's not normal, and probably why I can't find it.  I reloaded the software (currently 5.0 at the club), that didn't change the behavior.  Is there something else I can do to get it's attention?  It's clearly not totally dead as I was able to successfully connect and load the software again.

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Hello John,

I had the exact same problem with my old TIU. Wouldn’t recognize any engines or commands from the remote. After two weeks of aggravation I just gave up and bought a new TIU-L. No problems since and the signal is far and away better than any previous version of the TIU.



Typically, reloading the MTH DCS software cures the problem.

When I first had this happen (25-blinker), this wasn't the case. In response to my issue, first MTH corrected my TIU's problem and then added code to the Loader Program to reset any TIU with an ID# greater than 5, to a DCS ID# of "1" during the TIU software updating process.

From page 175 of The DCS WiFi Companion:

There is one TIU problem that the author has seen on one occasion that has also been reported by a few other DCS operators. In this instance, the TIU’s DCS address becomes outside of the normal range, i.e., between 1 and 5. When this occurs, DCS Remotes will become unable to access the affected TIU. It is unknown, however, if the DCS Application is also unable to access the affected TIU since the author has not experienced this problem while using the DCS Application, and has not received reports from any other DCS Application users in this regard. 

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Barry, I remembered that it was mentioned loading the software should correct it, that's why I tried it.  I'm a bit bummed that it didn't change the symptom, could it be that I need to load later software?  I can certainly try that, I can always drop back to 5.0 as that's what all the club TIU's and remotes are running right now.

FWIW, I am using the current loader, at least the last one I've seen.  If the loader is supposed to be fixing this, I guess I may have a bigger issue.

DCS Loader


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John,  If you can't load software and the TIU continues to have random numbers greater than 5, the memory chip has failed.  It is a PITA to change and it is very easy to lift traces that then require much more labor trying to jumper back if even possible.  Additionally, the memory size matters with other jumpers installed.

In my opinion not worth it on a rev G.  But if you want to go for it, call into MTH to get the specifics.  I have done it successfully once, and have since decided not worth the effort.  G

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Since this TIU already has a cooked VAR #1 channel (the brown trace under the PCB), and now this issue, I won't be spending any more time trying to fix it. I got it free, and I've kept it running for quite some spell, it's time for it to retire.

I know my limitations, I stick to .095mm pitch parts or larger for the most part.  Smaller chips with a finer pitch I will tackle, like the PS/2 amplifier chip.  I just don't bother to attempt larger parts with .065 and smaller pitch, just too stinkin' difficult to get them on without killing the board or the chip.

Somewhere I have a dead TIU, just can't lay my hands on it right now.  If I find it, I'll think of you.  I don't know what I'll do with this one, though I'm guessing that it's destined for the junk box from the looks of things.

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Alan Mancus
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