Thank you Costas and Tom.
I have attached a photo of the crocodile chassis displaying the wiring and decoder mounting board.
From the original mounting board, 3 wires are taken to the sound board. These are orange, white and black.
From the sound board two white wires go two the speakers.
Which of the three input wires should be used to connect to the speaker.

Also a great idea about mapping the AUX1 etc from the original board. The idea could be used for matching other functionality in future projects as well.

Best regards to both of you
David

Okay.. I have the sounds and motor working correctly, but I am still struggling with the red swiss light. I have confirmed that there is a red led and it seems to be powered or grounded through a blue wire. However, I can't determine the correct auxiliary and I am unable to link it properly using a CS3.

Some images...

The CS3 hardware information



This is the blue wire on the decoder base - it seems to connect to pin 20 on the 21 pin socket.



This is the two blue wires on the middle board. Left lower wire comes from the above-mentioned board, while the right-hand one goes to the LED lights.



This is an image of the LED board - rear one.. The blue wire is connected to a pin above the gray one (i.e. they are separate pins)



This is the CS3 screen for the current settings for F0. These lights work correctly.. Three whites in the front and one white light at the rear right side.



This setting is from the default project download from Marklin for F1 (Swiss Lights). I don't think that there is an AUX 3, but I tried AUX 1-6 in that position with no change..



I know that something is not set correctly, but I can't figure it out.. I wish that I had access to a 39563 with a working original decoder so I could see how it is set up in the CS3..

Any thoughts?

yes, it’s a journey , I'm currently struggling on a journey, with another project with undocumented functions in the MSD3 decoder.

whats a strange is this picture from 39562 on the moba-hgh.de site

it seems like the blue wire in your locomotive is brown and yellow in this picture, that indicates Aux 3. But then the decoder board might be different.

Post initiated on 08-Aug-2022
Dear All,
I am in a similar fix, in my case the Sinus Motor bus, just snapped out of the decoder when i tried to plug the new marklin msd/3 60977 decoder to the original mother board and the motor STOPPED running.....then i had to buy a new DC brushless motor and replaced it.

For your info i soldered the Pin - No 18 and 19 To the Motor terminals and the motor is running, i kept the other wirings and the onboard circuits intact to save the Swiss Headlights, Sound & Pantograph Operation switch.



This is the video after doing the work, as it would appear, the sound features not fully functional and also the Red color break lights not visible.

Tonight i am going to trouble shoot this with CS5, to restore the sound and headlights by playing with CV values, i have given good reading of all of your post, hope it will help me to bring back the engine alive completely. i will keep you all posted with my findings. _/\_

Updated as on 11-Aug-2022

Hello everyone,
Further to update on my previous note, i couldn't succeed in retro fitting a DC - Motor to the original Marklin 39562 mother board with 60977 decoder, Apparently the sound did not come through and the motor in itself was not driving with full efficiency.

So i decided to strip all the wires to barebone and connect the 60977 mSD/3 decoder with motor, supplied speaker and the existing led lights. But here also there was challenge as the lighting had separate control circuit.



The control circuit on the left in pic was serving 3 purpose -
1.Providing Connection to Pantograph and Centre pickup shoe
2.Swiss LED Lights as was mentioned earlier in the post by bph was very useful study the functions of the LED, reposting the same link for ease of reference (Courtesy bph: https://moba-hgh.de/mode...weizer-lichtwechsel.html
3.To receive the Orange and Brown wires from Loco chassis and connect to decoder.

The only reason to keep this secondary board was for the 2nd point. (Switching yellow/red combination)

Here is the wiring connection diagram i made, so that it could of some use to people who want to retro fit Motor and Sound functions into the complex SSB 6/8 crocodile loco Marklin 39562



The only hurdle i faced was, the 2 wires from the Light Control Board (Purple and Brown with yellow strips - refer picture), There is no option to connect this wire, i really wondered where to connect it ?, if left open without any connection what would be the impact.

So i went back to the old Mother board and traced where these wires connected.





Here if you observe the purple was connected to Ground - Pin 20 of the Decoder and Brown-yellow was connected Indirectly connected to Aux 3 Port via what appeared to 3-pin MOSFET transistor, which is usually used to drive SMD LED's. Since it was connected to Aux 3 Port, it gave me relief that this was only optional and i can do away with its functionality and and decided to leave the Purple and Brown-Yellow wire open.

The Central Station, i only calibrated the CV 51 value to set it to 5 - (Soft DC motor)

Here is the videos of the loco test run. The pickup shoe and motor & gear mechanism did face of runtime challenges, but functionally its working now.


With Pantograph connected. Slow Operation Mode.



Thank you _/\_

Regards,

Senthil

Edited by user 11 August 2022 10:47:55(UTC)  | Reason: Not specified