Some good questions..i am staying tuned to this post but just to clarifyand get the ball rolling..you are running DCS with a TIU and have tried both the AC and DC into fixed 2?

Keep in mind fixed 1 or aux power supples power for TIU operation.

Hi Willygee, No, HO is strictly  DC. When Ihad the O gauge setup , I used the TIU  with AC. No problems.  But now, with using the DC cruet , it's not working. So looking for simple but accurate help big time.  

willygee is noting you need to apply power (whether it be AC or DC) to the TIU itself via the fixed 1 or aux inputs.  is the RED LED "ON" showing the TIU itself is receiving power?

I use dcs to run my Ho MTH locomotives and have no problems. My TIU is wired thru he fixed and out the fix on the other side. I also use the old bulb trick connected to my power panel where the TIU is connected to. It improves the dcs signal. 

Check your power pack to make sure it is working and you have the wires conected properly. If nothing is adding to your remote switch the wires on the TIU ( both sides) and give it another try. 

If the the engine is starting up when you apply power just means the engine does not see the dcs signal. 

Thank you david1  Going to give it a try now. Going to say now that it is nice to have a place to go when you have a problem and good people respond with helpful information and not smart *** remarks. It's not the site, it's people like we say in the Wyoming Valley " YOUZ GUYS" LOL  that make it so.  
Thanks again. 

No david1, The red light is not on. Can I run a second set of wires from the variable terminals to the fixed aux input terminal. ?? I only have  acc (2)screws and var(2) screws and what's the old bulb trick??

The Lackawanna has been found and is running and sounding like a champ. Once again guys , THANK YOU Both. But david1, still want to know what the bulb trick is????

Great, fixed.... The tiu is just a radio or any other electronic device  , it has to be turned on to function.  2 ways  to do it..... Power to fixed 1 or an aux power supply.

Where ever you have the wires from the fixed out from the TIU connected to, attach a socket with a bulb. It only helps to increase the signal For better running. When I checked the track signal on my layout it increased from 5 and 6 to a solid 10 everywhere. 

As in a small ho street light bulb ?  Can you post a pic ?   Thanks.