problem with DCS controlling Legacy locomotive

[Joe S128]

Hi, I'm new to the forum-

I just bought my first Legacy locomotive and I'm having an issue- wondering if anyone has had the same problem or suggestions for fixing it.

I have a temporary layout set up with MTH DCS (ver. 4.0) and a TMCC command base connected with the TIU/TMCC wire. The ground is going to the common terminal on my ZW. There are two separate loops of track but they are wired together (star pattern). I guess you can say the computer would view this as one track: ZW-Fixedin1-Fixedout1-both loops. For the most part all of my TMCC, PS2, and PS3 locomotives run fine. The problem is the Legacy locomotive (Chessie GP30 from the 6-31735 set). The commands are slow and intermittent. I have to press the bell button about ten times to get it to come on and off. The horn does the same thing and when it does work, I only get a few short blasts no matter how long I hold the button on the DCS remote. Speed control is lagging too. 

Any suggestions?

I'm running an earlier TMCC C420 (no odyssey) on the other (connected) loop could this might be interfering? Could it be the GP30 or some mistake I have made? Everything else is fine and I don't own any other Legacy locomotives yet to compare to.

Thanks in advance-

[dbaker48]

Can you run the TMCC engines with your DCS remote?  Do you have the TMCC/DCS interconnect cable?  This is a special cable you need that connects between the Command Base and the TIU.

[Joe S128]

Don, thank you, and yes, I have the cable connected between the TIU and Command base with the ground wire connected from the command base to the common terminal on my ZW. All of my other TMCC locos run pretty flawlessly- its just the Legacy loco that I'm having this issue with...