MTH P5a ps3 upgrade

Dave,

Second issue: If I remember correctly, the speed sensor is on the motor without the traction tires.  It needs to be moved to the motor with the traction tires.  Later P5s have this modification.

Try this for the 1st issue.  Start the engine up in conventional, as soon as you hear the startup sequence, do the 1 horn, 5 bells to reset the engine.  This needs to be done quickly to catch the engine before is has a chance to move.  You should hear the 2 horn blasts for confirmation.  Then try and see if you can change directions.  It might take a few tries to get the timing right.

Or use the unlock sequence as it moves around track at low voltage (9-10V).  G

Thanks for help, seems i got it reset for conventional running, N,F,N,R.  Not sure how that happened but it works.  

2nd issue:  i still don't understand why just the motor with the traction tires is turning while the other has stopped.  I always thought both motors run at the same time.  It is definitely caused by uneven track and not the fault of the engine.  It just takes light downward pressure on the engine to make it go again.  This may be where removing the spring in the front truck will help as previously suggested.

also i am not going to remove the shell to check for the tach reader, because of risking pinching a wire.  Under DCS it runs great except for this one issue which is mostly a track problem on my carpet central.  
Thanks again

Dave,

As Ron said above; Only one motor has a speed sensor on it.  The board does not recognize that one wheel set is slipping or not moving.  It sends the same DC pulse to both motors based on the information it is receiving from the tach reader.  There is a physical condition allowing one set to move while the other is binding up.  (your uneven track, a switch, curve too tight, even smoke fluid or oil on the wheels will cause this)

FWIW, Lionel Legacy and TAS EOB work the same way, if the motor with the tach reader doesn't have traction, you ain't going anywhere.