help me identify the usb cable pinouts

khankll

Feb 6, 2011
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hi i have usb cable but its colouring scheme is not standard .it has 4 wires red,white,green,blue.. how to identify which one is +5v and ground,and D+,D- ?

i have checked some vltages the voltage accross the green and blue is zero, and if i connect the ground probe of multimeter to white then any of the remaining three wires gives me - 4.8 volts - minus 4.8 v)..

thanks.
 

davenn

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Sep 5, 2009
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the colours are meaningless to the rest of us ... the manufacturer could have used any colour of choice. What pins of the connector do they go to ?

here are the standard USB connector pin ID....

attachment.php





Dave
 

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khankll

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thanks but i know which pin is for what .. what i cant distinguish is that since the individual wires connected to each pin is hidden within the rubber sac and then in the plastic tubing so its impossible to trace eaxxh wire back to its pin within the connector.. i only have to rely on voltages..
and if i place one probe on white then placing the other at any of the three wires gives exactly same volts 4.8v ..

besides there are other wires combinations that also gives 4.8 volts and that are constants .. i.e not like 4.8 volts one moment and something else he other..
 

khankll

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here are some readings that i just carried out.

with white cable connected to ground probe of dmm the coltages are
green -4.8 v
red -4.8v
blue -4.9 volts


with green cable connected to ground probe of dmm the coltages are
red -.1 v
blue -.1 volts
white +4.7 volts

with red cable connected to ground probe of dmm the coltages are
green -.03 v
blue --.03 volts
white +4.84 volts

with blue cable connected to ground probe of dmm the coltages are
green +.01 v
blue +.01 volts
white +4.94 volts
 

Resqueline

Jul 31, 2009
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Wherever you get the highest voltage is likely to be the power supply. But what's the reason you just can't ohm it out?
 

khankll

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Wherever you get the highest voltage is likely to be the power supply. But what's the reason you just can't ohm it out?
i dont understand the second part of ur question ?

i want to confirm the pinouts....
 

khankll

Feb 6, 2011
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so guys i have confirmed that the white is +5v and blue is ground.

thanks to all for ur help..
 

CocaCola

Apr 7, 2012
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i dont understand the second part of ur question ?

i want to confirm the pinouts....
You check continuity between the end of the wire and the connector with a Ohm meter, you do this for each wire until you map them all out... Each connection on the connector will only connect to one wire, so when you see continuity you have found the common connector/wire pair...
 

khankll

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^^ thanks bro cocacola i sorted it out long time ago..
 
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