Fastrack Switch has problem that I cannot figure out - SOLVED!!

Sounds like you've checked everything fairly well.

1. Maybe try connecting a known good remote.
2. With no remote connected, manually activate the anti-derail feature in both directions to see if that will move the points.
3. Next check continuity individually between the Common and NO and NC terminals on the micro-switches when the micro-switch levers are in both positions.
4. If the micro-switches are good, I'd swap in a new motor driver board; cs-691TRC4A01-p

Here's the link to it on Lionel's Parts site:

https://www.lionelsupport.com/...FASTRACK-SWITCH-TMCC

I've had the same exact symptoms.  Once it was a wire separated from the micro switch.

Another time, the board was partially bad and was only faulty in the ways you describe.  I think it may have been caused by voltage spikes from a derailment.

@VinceL posted:

I have an 072 Remote/Command Right Hand switch that is exhibiting a problem that I have not previously encountered.  It is using track power.  If the switch is in the thru position, the remote lights up green and I get +5 volts on the yellow connection.  If I throw the remote to turn out, the remote has both the green and red lights on and I get .02 volts (basically 0) .  I cannot use the remote to switch back to thru.  Using a CAB1L I have the same problem.  I can switch one time to turnout, but cannot switch back to thru.  The microswitches are both aligned properly and close completely when in either the thru or turn out position.  I have tugged and prodded all of the solder joints and can't find any that are loose.

The switch is close to 10 years old and was working fine before I started pulling up track.  The only reason I found the problem is that as I pull them up, I put in a 22uh choke to prevent possible DCS interference.  I used to use aux power, but for simplicity of wiring the revised layout I decided to switch to track power.

Anybody have any suggestions on what else to check?

One thing to check- you may have a short to the metal back cover between any 2 of the contacts. As part of my bulletproofing sequence of mods done to any fastrack switch, I insulate the back cover area using a few layers of material so that the sharp and often updward facing (when switch is facing upside down).

It's possible the main control board was damaged by such a short, or a short is causing your unable to switch in one direction symptom.

And yes, kicker being the older model- lionel over time changed boards and connectors and might not be able to easily retrofit a new board in that old switch. It might just become "spare parts" for your other switches of that age.

Vernon, thanks for mentioning that the replacement motor control boards are different. However the only functional difference is the TMCC Radio Board connectors and pin-outs are different, (lower left 6 and 5 pin connectors, respectively).  As can be seen in these images, all other connectors are the same, pin for pin.

On top is an older type 691-TRC3-F       Bottom is a newer 691-TRC4-A00 Rev.4 (purchased in 2021)

So, unless there is another cause for the problem, the newer board will restore all normal functions, including the anti-derail feature, of the turnout in an older FasTrack Remote Switch using a wired remote.  I've tested and confirmed this.

For regaining TMCC control, there are workarounds, such as wiring the switch into a LCS 6-81639 ASC2.

Steve and Vernon, thanks for your replies.

I did check the microswitches and they both test fine.  I tried activating the anti-derail function and got the same results as with the Remote and  CAB1L.  I am doing all of my testing with the switch upside down without the bottom plate.  So, I'm not having any problems with a short to the bottom plate.  But, it could have shorted at some time and fried the board. I do not see any signs of anything being fried.

I am sure I have the older motor control board (my trains are in another building on our property so I'll check tomorrow).  Steve, let me see if I am understanding your comments about the new vs. old board.  Assuming the problem is with the motor control board, if I order and install a new board, all switch functions (including control by the remote) will work correctly.  But, it will not interface with the TMCC board that is currently in my switch.  But, I could use an ASC2 with it to restore command control.  Is that correct?

Fortunately, I have 2 ASC2's because I do have some Remote only 072 switches.

Would it be worth it (or even possible) to get a new TMCC board for the switch to restore full command control?

@VinceL posted:

Would it be worth it (or even possible) to get a new TMCC board for the switch to restore full command control?

Yes you can buy the parts- next problem is the wiring harness between the 2 boards- as Steve eluded to.

https://www.lionelsupport.com/...STRACK-SWITCH-TMCC-B

https://www.lionelsupport.com/...FASTRACK-SWITCH-TMCC

Yes, you can easily use an SC1 or SC2 or newer ASC2 to control. That's what in some ways the original TMCC board is, 2 triacs that fire to short either the red (turn) or green (straight) wire of the controller to gnd (black).

Much to my surprise, this switch must be one of the more recent switches that I have purchased.  It has the current board.

I have just placed an order for the board.  Hopefully, this is the problem and the new board will fix it.  If not, I will have a spare board.

Thanks for the help.

One thing that fixes random oddball issues with Fastrack switches is soldering all the crimps under the covers.  Relying on a folded tab of metal for reliable contacts is foolhardy, but that's what Lionel does.

Because of loose metal crimped connectors I had found on several Fastrack switches on my first layout before I started putting down this layout I took the backs off all the switches, soldered all the crimp connectors, covered any exposed metal inside with electrical tape to prevent any shorting to the back cover and tightened all screw connections to wires. Also check to make sure Fastrack switches aren't miswired from the factory. Since this switch used to work correctly before this wouldn't be an issue on this one. For the cost of Fastrack switches Lionel should have their supplier do more secure track connections than a piece of crimped metal together. If I knew then what I know now, it would had been Ross Switches and Gargraves Track all the way. Unfortunately I can't afford to start over again so this being used Fastrack from my first layout, now I've soldered jumper wires between each piece of track and feeder wires to every six sections of Fastrack to help avoid bad connections with it on my conventional 12' x 6' "L" layout powered by 2 independent tracks MTH Z-1000 Transformers. Fastrackis a royal PITA!😤

Lionel shipped me a replacement board for my switch very quickly.  Today I installed the new board and still have the same problem.  I have poked, prodded, visually examined, and measured resistance for every connection I can think of checking.

I had previously tested the microswitches to make sure they were closing properly.  For each microswitch I get the following results:

If the microswitch is closed, both show that the Yellow and Blue connections are shorted together.  Yellow to Red and Blue to Red are both open circuits.

However, if the microswitch is open, I get different results.  With one microswitch in the open position, The Yellow and Red connections are shorted together.  Yellow to Blue and Blue to Red are open circuits.  The other microswitch in the open position shows that Yellow and Blue are shorted together.  Yellow to Red and Blue to Red are open circuits.  Hmmm.   I would think they would be identical.

I have checked very closely to make sure the solder connections on the microswitches are clean with no stray wire strands or solder connecting between terminals. 

I am now thinking that one of the microswitches has its wires crossed.  The switch used to work; I can't imagine what could have caused this.  Can anyone confirm that the readings I am getting are not what they should be?

Looking at the Lionel Support website, it looks like Lionel calls these microswitches cherry switches.   Under the exploded parts diagrams for the switches, it shows the cherry switch as part 3, but is unavailable.  I did find part number 6102045318 for a 3 position cherry switch with wiring harness for Fastrack switches.  Unfortunately, the photo doesn't show the microswitch (cherry switch); it only shows the wiring harness with the connector.  Does anyone know if that is the part I need to replace the microswitches on my switch.  If so, I will buy a few of them and replace both microswitches on this switch.

Vince, I'm sorry for your frustration.  In your first post, you stated that it "was working fine before I started pulling up track."  I've taken apart my share of layouts, including some with Fastrack.  It's a physically vigorous effort that involves pulling, bending, twisting, etc.  Switches are the worst because you often have to loosen several sections of track in all three directions before they can be removed.  Is it possible that this particular switch got flexed or pressed down upon, in a way that cracked a board trace, or pushed two metallic contacts together that should be isolated?

It's ultimately a collection of parts.  The only thing I can think of is to swap sub-assemblies with a known good switch until the problem goes away or transfers to the other switch.  Good luck!

Thanks for the reply, Ted.

I have used a VOM and tested every connection that I think of or can get to.  I just installed a brand new board in the switch from Lionel today which didn't solve the problem.  The only other circuit board is the TMCC board.  Just to be sure, I disconnected the TMCC board connector from the new motor driver board.  As I suspected, it made no difference.  I guess I will open up another switch (which I recently removed but tested since I am installing 22uh chokes in the switches as I remove them).  I will check the 2 microswitches to see if they report the same different results as this problem switch.   Depending on the results I will probably move some microswitches around.

Once I get confirmation from Lionel support that the part I found is what I am looking for, I will buy a few of them.  Those microswitches seem rather fragile.....always good to have spares.

I opened up a known good switch.  After testing the microswitches, I discovered that both give the same readings open or closed.  I pulled out one of the microswitches and plugged it into board connector on the bad switch.  Based on my testing I picked the connection for the microswitch that I suspected was bad.  I applied power and hallelujah the switch worked perfectly.

I just ordered several microswitches, wiring harnesses and while I was ordering, I decided to order a few of the tiny screws for the microswitches.

I'm not a very good solderer so I'm not looking forward to soldering the wiring harness to the small terminals on the  microswitch.