How to find keyboard cable + - ends

[hummerjanne]

How to find keyboard cable + - ends My question is yes, the cable is broken and how can I find the + - ends?

[Swake]

You'll have to give more details about what keyboard it is and how it is connected

[ebastler]

Assuming it is a USB connection, which is by far the most popular today -- did you try Google or Wikipedia?
https://en.wikipedia.org/wiki/USB_hardware

If by + and - you mean the +5V supply voltage and GND, they are on pins 1 and 4 (the two outermost pins in a USB A connector). If you mean the data lines, D+ and D-, they are on pins 3 and 2 inbetween.

[hummerjanne]

I solved the problem but I saw that no part was working on the keyboard motherboard except the IC silicon so I replaced it, I used the LED to find the +- cable and found it this way. The problem was with the keyboard motherboard, not the cable. Almost most of the parts did not work. I removed the SMD parts and replaced them with high value resistors and capacitors.

[ebastler]

You mean, all the passive components (resistors and capacitors) on the keyboard's PCB were bad, but the active IC was OK? That is very unlikely. Maybe there was just a single bad component or a bad solder joint somewhere?

In any case, glad you got it back into working order!

[hummerjanne]

Yes, the resistor was not working. It connects to LEDs. Luckily I solved the problem, but one thing I noticed was that it wasn't giving any value. The resistance was showing 0 and the multimeter was beeping. The capacitor was not giving any value.