Skip to main content

Working on a TIU, Rev I3 with 6.1 software loaded. 

The TIU blinks twice when powered on.  Can not communicate with Remote  "Out of Range"  is the message.  Power up on Aux port and tether the remote:  "TIU Error" is the message.  Opened the TIU and checked all 4 diodes - good.  All four  20 Amp fuses ok.  RF module is correctly seated.  Checked "A" voltage on the RF module  4.8.  Checked "B" voltage  3.3.  Both should read 5.0 on a good RF unit.  Could not read "C" voltage, the component is too close to others.  Get good output on Fixed 1 and 2 ports.  Trouble shooting per our Tech Service Manual.

Do not want to replace the RF unit yet and possibly ruin a new RF unit.  I have not ruled out a software glitch because I can not load 6.1 to this TIU.  Using MTH DCS Service Loader 5.0, I can not communicate with the TIU and that is after a check for Com 3 was good.  The voltage regulator near the RS-232 port shows no blistering or abnormal condition.  No smoke or any smell is coming from the unit.

Made sure the remote was set to channel 1 prior to all testing.  Maybe John, Jon or Don can offer some guidance.

Bruce,  MTH ASC Tech

Original Post

Replies sorted oldest to newest

Is there any documentation on this fix?  Was it for a specific version of the TIU?  What was it supposed to fix?

This was before I was an ASC tech.  The fact that there is no documentation from MTH should not surprise you John!  LOL  You might give Don a call.  He was most likely around back then.

This fix is specific for this TIU.  I was also told that not ALL Rev I3as needed this.  I do not know if that is true.

I can tell you that I steer clear of these TIUs.

Hope this helps!   

Last edited by David Minarik

There are several fixes for those I units, hence all the mod # on them.  They do predate become a tech just like Dave mentioned.  There are probably ASC updates on them, and I may have one or two, but not sure where.  Those fixes are typically about signal strength, I also believe there was a jumper depending on which memory chip it got.

Bruce, have you gone through the TIU trouble shooting in your manual, there are voltage checks on the Receiver board you can do.  G

Add Reply

This forum is sponsored by MTH Electric Trains
OGR Publishing, Inc., 1310 Eastside Centre Ct, Suite 6, Mountain Home, AR 72653
Link copied to your clipboard.