Cannot communicate with TIU without tether

Can't miss it, it's the little board with the antenna wire on it.

Bruce,

If you have a copy of The DCS I Gauge Companion 2nd Edition, the answer to your problem is found on page 155:

Since reseating a floating transceiver board in the TIU is considerably easier than reseating the transceiver board in the DCS Remote, it's suggested to check the TIU first by proceeding as follows: 

• Remove all connections to the TIU 

• Turn the TIU over and remove the 6 Philips head screws that hold it together 

• Turn the TIU right side up and remove the top half of the case 

• Facing the channel input ports, the transceiver board is on the lower right side of the case. It will have a short black wire connected to it. This wire is the antenna 

• Press down gently on the transceiver board to reseat it. Also ensure that the black wire antenna is lying flat. Do not under any circumstances lift up on the transceiver board or antenna! 

• Place a piece of soft, nonconductive spongy material above the transceiver board so that it will hold the board in place when the top of the case is replaced 

• Replace the cover, turn the TIU over and replace the screws 

• Turn the TIU right side-up and reconnect all wires to the TIU.

There's a picture of the transceiver board on page 156:

This and a whole lot more is all in "The DCS O Gauge Companion 2nd Edition", now available for purchase as an eBook or a printed book from MTH's web store site! Click on the link below to go to MTH's web page for the book!

Thanks John and Barry.  I removed the top this morning and reseated the board - all works now.  I cut up one of my wife's diswashing covered sponges and glued to the top cover.  Will replace the cover this PM.  Thanks Bruce

Barry had the "official" version, mine was the Cliff Notes version of the repair.