What kind of resistor do I need here? I know the capacitor on C6, but what number is on the resistor? R18? And ohm?

 

What happened to the original?
Just guess work at this point without an identical board.!!
Max.

 

It's impossible to read anything from the original resistor as it blow up...

 

So you imagined that we could reach back in time AND read the mind of the original designer.

 

Looks like its a smpsu, using a lm3???

 

Looks like its a smpsu, using a lm3???

Boy that was helpful!!

 

If you don't have any info on the circuit, then anything we say is pure guesswork.

 

Ok. What should I do now? Can I test with a random resistor?

 

Do some reverse engineering of the circuit and it may be possible to suggest a value.
Max.

 

Do some reverse engineering of the circuit and it may be possible to suggest a value.
Max.

What @MaxHeadRoom means is that if you examine the board carefully you may be able to create a schematic. From that schematic, the design can be compared to similar designs, and the value of R18 can be determined with some level of precision. Are you up to the task? It won't be easy.

 

By the wire gauge and outline size and the proximity to the missing electrolytic, I would guess it is in the circuit in or around the power input /DC supply/bridge rectifier part of the charger.
Max.

 

Is it dangerous to try with a random resistor value?

 

Is it dangerous to try with a random resistor value?

It is much better to use an educated guess based on the reverse engineered part of the circuit, rather than 'Random selection'!
Max.