I use Train Controller Gold and Marklin C-track for my layout. Long before I became aware of the 74490 turnout motor problem I decided to go for turnout position control. For track occupancy I use the LDT Opto variant of s88. There I also found a description of how to use them for turnout position control. No new equipment, just more of the same. However, in my opinion, TC doesn’t go all the way - but it has useful tolls. This is what I have done.

Two of the s88 Opto exits are connected to the blue wires to the turnout motor. When the turnout is in a proper position one of the indicators shows connection to power/B/red while the other is turned off. This gives the following possibilities.
I1 on and I2 on switching going on (or motor/turnout not working properly)
I1 on and I2 off turnout in position Thrown
I1 off and I2 on turnout in position Straight
I1 off and I2 off system error (no power to the turnouts)

In TC I have use the I1 off for straight and I2 off for thrown. A Flagman is triggered if I1, I2 or the turnout position is changed. Condition (for not OK) is I1 on and Straight, I2 on and Thrown or both I1 and I2 off. I have recorded this flagman for the turnout. It turns red when not in position. I have also set the flagman as occupancy indicator for the turnout. I don’t allow my schedules to enter occupied blocks/routes and this gives me a chance to get the turnout in position manually.

Given what I now know about the Marklin 74490/74491 motors, maybe I should have used the shorting of the micro switches method and hoped for reliable function instead. Now I get early indications of a problem.

Warning: for tracks the connection is with ground/0/brown and I don’t know if other s88s can cope with power/B/red.

blid