TMCC Locked in one Direction Question

CHeck that the PGM / RUN switch is set to RUN. 

Thanks Marty.

Trying to help out a friend here.....says the switch is in RUN.

Engine continues in one direction only, in conventional, which is the only way he runs.

I did a search and came across this information.

"To lock a TMCC engine in one direction for conventional running......let the engine proceed slowly in the desired direction and while doing so....slip the RUN/PROG switch to PROG."

If this is so, how do you go about reversing this procedure?  Just back to RUN?

Thanks Guys

Dave

Soo Line posted:

Thanks Marty.

Trying to help out a friend here.....says the switch is in RUN.

Engine continues in one direction only, in conventional, which is the only way he runs.

I did a search and came across this information.

"To lock a TMCC engine in one direction for conventional running......let the engine proceed slowly in the desired direction and while doing so....slip the RUN/PROG switch to PROG."

If this is so, how do you go about reversing this procedure?  Just back to RUN?

Thanks Guys

Dave

Yes, that is correct

Thanks Chris

I now have the engine in my possession......K Line  K25181  CP  F7  AA   TMCC - no cruise.

I've tried everything I can think of.

In command, all is well.

In conventional,  it will work fine in forward only......Cannot get it to reverse.

I did a TMCC Restore Functions using code 2 and no change.

Can anyone shed some light on this issue for me.

Appreciate the help.

Dave

Put the switch in PGM mode and try it. Maybe the switch was installed backwards.

Thanks Roy

No luck on that effort.

I've done all the research I can and I have absolutely no idea.

Even if it cannot be fixed.....my curiosity compels me to search for the reason for this issue.

Appreciate all the assistance.

Dave

Swap out the R2LC, it's the most likely suspect.

Make sure the problem isn’t your transformer. Certain modern electronic power supplies sometimes don’t fully go to zero volts, allowing just enough power to “hold” an electronic reverse unit in position.

To test, try cycling your reverse unit by disconnecting and reconnecting one of the two power wires to your track. If you find that your reverse unit cycles reliably in this manner, the problem is your transformer. 

TRW

TRW  Thank You.  Great to know for future reference.  Much appreciated.

GRJ - John was correct on this issue.  I had a spare board in my parts drawer and it did the trick.  The engine now runs well in both Conventional and Command.

Thank You John for your assistance.

I guess what is confusing to me is:   If the R2LC controls the FNR in Conventional and fails, how does it successfully control FNR in Command?  Just a part of the board fails?

Again, Thank You to all who took the time to assist.

Without the talent on this forum, I would still be in the dark ages 

Dave

Soo Line posted:

I guess what is confusing to me is:   If the R2LC controls the FNR in Conventional and fails, how does it successfully control FNR in Command?  Just a part of the board fails?

That's an easy one.  The conventional operation depends on sensing the voltage drop on the track, command operation is totally directed by the data coming in the TMCC command signal.  Totally different operation, the sensing of track voltage isn't happening in command, the circuit that senses the transition is not in use or being monitored in command mode.

It's the same reason that in command the RailSounds board doesn't see the DC offset on the track, only when there is no TMCC signal present.

Understood.

Thank You for the explanation John.

Dave