Can't find TIU when two or more power supplies power to the TIU

If I understand you problem correctly, not sure I do?  The TIU needs power to operate.  It gets that power from either the Fixed 1 Input or the Aux Power port on the TIU. Sounds like you are removing power from Fixed 1 Input and the TIU is not getting powered.  

If you are using more than 1 TIU channel you should be powering your TIU from the Aux Power port. 

not exactly.  I'm not using an external power supply (but I might try that to see what happens).  power is always supplied to fixed 1 but even with no outputs on fixed 2 and the variable output, when power is supplied to both Fixed 1 and any other input it "can't find the TIU".   

I thought I might be reading that incorrectly. I think I get it now, sounds like an odd problem that I don't recall ever hearing about before?

I'm afraid I don't have any other ideas on this one? Maybe someone else will be along that can diagnose the problem or at least offer some further suggestions.  

Using Aux power with external power supply is still recommended when using multiple TIU channels though.

I found a router power supply that would fit the jack and with external power it allows me to operate Fixed 2 but I still get the same issue when I try to put power to fixed 1.  If I apply power to more than one input the iPAD says "NO TIU FOUND", the RF Handheld is fine.  But at least I can power the other tracks one at a time! 

So everything works normally in any configuration with the DCS remote? But when using wifi with an ipad you have problems anytime you power more than one TIU channel? Do I have this part correct? If so, it sure seems odd to me.

I have the WIU and Deluxe App, tried it briefly and went right back to the Remote which I much prefer. I have very little experience using the wifi setup.

Only thing I can think of is to make sure you have the most current firmware in your WIU. There was one update early on that fixed some problems with the first release. But, I haven't stayed current with any further updates, there could be more? 

Sorry I don't have more to offer here.

I think you'd have to troubleshoot a little more. Maybe something is drawing the signal down for some reason? Do you have TMCC/Legacy engines or powered cars on the rails?

Remove them to test. I bet you need chokes on them.

Can you disconnect the TIU totally from your layout and try hooking up 2 spare pieces of track, one to channel one fixed and one to another channel. Then try to power both with a single MTH engine on each.

 I have a feeling your layout is back feeding power from some where? Did this issue just pop up? Did you just change any wiring? Do you have the polarity correct on all channels?

Are you sure that outmon the layout theremis no interconnection between the channels--that thetracks controlled by each channel are electrically isolated from other tracks?

interesting.     

Based on comments received I set up  two short tracks and all works fine.  so that leaves me to believe I'm back feeding.   So my next and question is the tracks are center rail separated  but not outside rail.  should I cut the gar graves pin out of the switch (Ross and Gargraves switches)?  or should I go a foot away on the branch lines (TIU variable 1&2) and isolate all three rails?  

I appreciate all your great ideas and suggestions.

Do not break outside rails.  Many Gargraves switches do not have center rails connected under the switch.  I like that, because on my layout every switch ends 3 blocks.

 I use bulbs on my old TIU and just went thru this. I found a side of a switch was feeding thru that I thought was isolated. The bulb on the TIU output kept lighting until I cut that rail.

Cut the center rails on the branch lines after the switch. Your choice on exactly where. If it's easy to remove the pins and create a gap, do that.

Just so they don't back feed again to the other block.