DC to DC step-up converter + L298N motor driver: short circuit

I am trying to connect DC to DC converter and Motor Driver.

Connecting white wire to second terminal (next to orange wire) causes short circuit. I have tried to replace DC to DC converter to another one, tried also to replace Motor Drive, but the same result.

Am I doing anything wrong?

Can you sketch out how ALL the parts are wired together ?

From the photo is doesn’t tell much, and I can’t see a motor there either.
What’s the power supply?
What’s the DC converter rated for ?

Can you sketch out how ALL the parts are wired together?

I have not connected other parts so far: short circuit occurred as it is shown on the first picture.

I can’t see a motor there either

There won't be a Motor. L298N I need to control fairy lights.

What’s the power supply?

PSU output is 12V DC.

What’s the DC converter rated for?

DC-DC Converter should convert 12V from input to 35V in output.

On the sketch below the red wire causes short circuit when connected.

ok, good start.
Power supplies and DC converters are usually rated for the current they can supply continuously.

If you haven’t connected everything up yet, then a sketch of what you have connected - to get the short circuit… label all the connections.

What you have so far is only a starting point as a block diagram (not a schematic), and still shows motors…?

How do you know the red wire ‘shorts’?

Power supplies and DC converters are usually rated for the current they can supply continuously.

DC converter according specification handles max 16A on input and max 10A on output. PSU supplies 2A max on output. L298N module has specification on the Amazon page: as far as I understood it is also 2A max.

then a sketch of what you have connected - to get the short circuit… label all the connections.

Sorry, misunderstood you.

and still shows motors…?

On the diagram Motor 1 should be replaced to Fairy Lights, Motor 2 will not be used.

How do you know the red wire ‘shorts’?

When I plug red wire (on diagram above) to GND terminal of L298N module - it is sparking and smoking exactly in the place of connection.

By the way, I have tested voltage with Multimeter on OUT- and OUT+ (on DC-DC converter) - it is exactly 35V.

If you have questions please ask.

You seem to have connected the DC/DC converter to the 5volt logic supply of the L298 board (orange wire). More than 7volt on that corner terminal (5volt) will fry the L298.
The 12volt motor terminal is near the pin strip. Google "L298 board" (images).
Leo..

This is exactly why you need to plan - and sketch out your connections - assuming you know what voltages are required ‘where’…

If you post the connection diagram BEFORE wiring it up, we can often see problems before they happen.

Electronics is very logical and constrained by facts, that’s why accuracy & completeness are important in planning.

You seem to have connected the DC/DC converter to the 5volt logic supply of the L298 board (orange wire)

35V (output of the DC-DC converter) to 5V pin of L298N?

To power L298N board logic I use 5V+GND from Uno R3 connected to 5V+GND on L298N. The orange cable on photo in the first post is connected to L298N 12V pin. And both 35V and 5V has common GND on L298N board.

As said in the specification 12V pin of L298N accepts voltage 5V-35V if jumper is removed (behind terminals).

May be more ideas why it is still "shorting"?

Thank you.