Mth operating track

Obviously the control rails are getting constant power. I would unwire it and start over. It may be as simple as a wrong wire placement. Good luck.

Thanks. I triple checked the wiring  the uncouple feature works perfect  just the operating part something wrong.   

It is possible for the uncoupling to work correctly independently of the activating rails. The manual, including wiring schematic is available from MTH: https://mthtrains.com/sites/de...ction/40as19352i.pdf

I am  using  only dcs Remote to control. I have rewired all the operating tracks (4 of them) to the top photo diagram which is the  newest AIU I just purchased.  I no longer have constant voltage to the control rails. Uncoupling feature works great on all 4. But the unload feature does not work on any of them. Any other  suggestions  would be much appreciated thank you 

Nitelife09 posted:

...The problem is as soon as u stop on the track the cars starts operating on its own...

I tried wiring both ways and get the same result.

Nitelife09 posted:

 I no longer have constant voltage to the control rails. Uncoupling feature works great on all 4. But the unload feature does not work on any of them. 

I'm confused.  Initially you said the cars operate on their own irrespective of which AIU wiring diagram you used.  As others pointed out, somehow there was voltage applied to the control (unload) rails.

Now you say you no longer have constant voltage to the control rails.  What changed?  Do the cars still operate on their own?

That’s a good question. I had them all originally wired per the bottom photo. I deleted every thing out of the remote. Rewired each one to how the top photo  now shows. The cars no longer operated on there own. Ok good.  No if  I press the “on” or the “act” button I get the pulse to in couple but the cars do not operate 

Nitelife09 posted:

...No if  I press the “on” or the “act” button I get the pulse to in couple but the cars do not operate 

I realize you have 4 operating tracks and presumably you are using 8 ACC ports.  

Focusing on the pics you posted which using ACC5 (for unload) and ACC6 (for uncouple).  So apparently now you press "ACT" for ACC6 and uncouple works for one operating track.  But you press "ACT" for ACC5 and you get no operation for that same operating track.  Is that correct?

Just focusing on ACC5.  The only change in wiring is you moved the connection that was to terminal 2 over to terminal 1.   The wire(s) going to terminal IN has not changed.  

Are you confident you are pressing the "ACT" button for ACC5?  Do you hear a faint relay "click" from the AIU case when you press "ACT" and then another "click" when you release "ACT"?  I realize there are dozens of relays inside the AIU so you can't tell which relay is clicking on/off but you should at least hear a click.

Yes the paths are correct  you do hear a click when you push  “act” or the “on” button. The “in” terminal wire stayed the same.  The only thing I nocited when testing  is that the track wired to ACC 8, is when you press the on button the center coil of that track  stays energized until you hit the off button. The other 3 only get a pulse weather you hold the act button on or you push the on button . All four do click  when you depress the act or on keys. Sounds like the rely is working for all four.  Very puzzling. 

Nitelife09 posted:

... The other 3 only get a pulse weather you hold the act button on or you push the on button . All four do click  when you depress the act or on keys. Sounds like the rely is working for all four.  Very puzzling. 

Many troubleshooting approaches.  But if the AIU is not behaving as an AIU, I'd start with the AIU.  Since the AIU is "just" a set of relays, "what" you're controlling (i.e., whatever is hooked up to the 1-IN-2 terminals) should be isolated/independent of the AIU behavior.  I'd go one-by-one thru the ACC ports using a meter to confirm operation.  That is, 2-IN are connected when the ACC port is off, 1-IN are connected when while ACT is pressed or ON.   If an ACC port is momentary, it's behaving like a SW port which fires its relay for exactly 1/2 second when activating the STRAIGHT or DIVERGE.  If software/hardware in the TIU-AIU combo is "projecting" SW port behavior onto an ACC port then it's an all bets are off.

If this momentary relay behavior goes away when you disconnect the operating-tracks from the AIU, then I suppose there could be some kind of squirrel-ly interaction in power supplies.  

In any case, my approach would be as stated - disconnect the operating tracks and confirm the ACC ports are all behaving like ACC ports.

Thank you for the insight. Thats going to be my next move.  Thanks again