Hello,
I bought this tiny little shunting loco a few days ago, used but very cheap for 98€! Great price for a digital loco with Sound, Telex and complex LED head lights!

When the loco arrived and my wife was gone away for a while 😉, I had time to inspect this beauti a bit closer and realized, there is a cabin light assembled under the roof! Why that? There is nothing written about a cabin light of the Ue 499 SJ nor about any other variant of this model!

So, I started to disassemble the loco and right! There is a small circuit board under the roof, equipped with two SMD LEDs and a resistor, forther solder points for U+, two AUX ports for the two LEDs to switch then separately and a soldier point for the contact to the head pick up.



But next surprise: The little circuit board isn't connected to the four brass contacts, you can see on the next image:



Therefore, to enable the cabin light there is more to do than to modify the mapping. Furthermore, I had to check which AUX ports are already used by the other light functions and the telex coupler.

Next, I checked the mapping of the different functions to know, which decoder AUX ports are used:



I realized that there is no free AUX port available, except probably AUX5/6, but I don't know if they are connected, available and probably not amplified. LF/LR, AUX1-AUX4 are used for the complex head light mapping. And a test showed me, that the Telex in serial connected to one AUX port will have enough power to work, but it will reduce the total current through the Telex Coil. It seems to be a good idea.

Therefore, I decided to connect two of the Telex couplers to one of the two SUSI AUX ports and the cabin light to the other SUSI AUX port.

Here You see the wires to the two Telex couplers connected in serial:



And here I painted the new wire from the SUSI AUX port to the soldier point for the cabin light:



Next I soldiered wires to the LED circuit board, and because there is only one free AUX, I connected both LEDs together:



Back into the cabin:



Then, before the last assembling step, I soldiered the two wires to the two brass contact bar. Keep care to use the correct ones! One is U+, the other one is SUSI AUX:



After changing the mapping, and a first test, the next surprise, the interior lights are red:



OK, here a short demo video showing the different head light effects and the now working cabin light:

Very strange, adding something to the loco but not connecting it., shouldn't there be 2 resistors, if you disconnect the wires again and try to light up 1 Led manually and see what colour it is.
I have found Roco Vectron locos have led's (not mounted) for different versions of the Vectron loco.

John

The brown version Ub didn´t had radio control under era 3.
That´s way there is no red tail light for older version.
If you want cab lighting try ESU LED lighting for wagons.

Here’s a good picture from the real world:

https://images.app.goo.gl/uMRczrZD5Y33uLB98

Peder

I have no access to my Ub’s right now, but I think the four brass pins is for the taillights and probably also for the pantograph.

Peder

And this is how it looks like:

A couple of years ago I wanted to add telex to my NSB EL10 36334. It is the NSB version of the same type of locomotive, but it does not have the same circuit board as the 36350. From the factory, this locomotive only have a function for lights on or off without direction switchover. When I was trying to install the telex couplers I searched for solderpads connected to the aux pins of the MTC21 contact. I discovered that the the four brass pins was related to aux3, aux 4, the pantograph and common. The front and rear led panel had connection to front, rear, aux1 and aux2. I reassembled the locomotive and mapped the functions. Front/rear is high beam ligths, aux1/aux2 is low beam lights and aux3/aux4 is taillights.

I saved the telex couplers for another project since I was quite happy with the increased light functionality. It is strange that these functions had not been mapped at the factory.