X-360 PSU ( PWM IC not having vcc voltage )

[SM-Piyes90]

I have recently got my xbox 360 power supply blinking red and no output .

I opened it up and checked the pwm ic vcc pin , and i got no voltage on it .
So checked the startup circuit , found a bad resistor , changed it and the unit is still blinking red .

any one familiar with this issue ?

Model is HP-AW175EF3P btw

[stj]

Re: X-360 PSU ( PWM IC not having vcc voltage )

does the standby supply work?

btw, those psu's overheat over time because of dust in them.
whenever you get one - hold a vac cleaner against the vent holes at one end for a min
most people dont know they have a fan in them.

[SM-Piyes90]

Re: X-360 PSU ( PWM IC not having vcc voltage )

Actually before that happens it was a constant orange light with 5 vdc at the 1st output and no 12 v at the 2nd output , and i was able to see the console's 3 RLOD .

But now after removing and putting back some optoisolators ( for tests) , i get that blinking .

I guess the blinking means that the standby supply is working .

[kc8adu]

Re: X-360 PSU ( PWM IC not having vcc voltage )

iirc the light wont blink if 5v stby is dead.
did you jump red and blue?
that fires up the main +12.
most of the consoles are in rough shape now and not worth fixing so i use these power supplies to run radio gear.
edit.
now that we know it worked till you messed with it go double check your work.solder shorts reversed/wrong opto,ect.

[SM-Piyes90]

Re: X-360 PSU ( PWM IC not having vcc voltage )

iirc the light wont blink if 5v stby is dead.
did you jump red and blue?
that fires up the main +12.
most of the consoles are in rough shape now and not worth fixing so i use these power supplies to run radio gear.
edit.
now that we know it worked till you messed with it go double check your work.solder shorts reversed/wrong opto,ect.

Yes , that's my thoughts too .

[SM-Piyes90]

Re: X-360 PSU ( PWM IC not having vcc voltage )

Okey am back to my original situation with a constant orange light after resoldering an optoisolator pin, but still no voltage at the PWM ic vcc pin , i have to mention that i have found a 150 ohm resistor that was giving 700 ohms , but things are the same even after the replacements .

Any thoughts on this dear members ?

[stj]

Re: X-360 PSU ( PWM IC not having vcc voltage )

got foto's and the pwm part number.

[SM-Piyes90]

Re: X-360 PSU ( PWM IC not having vcc voltage )

got foto's and the pwm part number.

Its S2153D , i will upload pictures later .

Thanks in advance stj

[SM-Piyes90]

Re: X-360 PSU ( PWM IC not having vcc voltage )

Hi again and sorry for not putting any pictures yet , i am still waiting to get my camera from a friend .

Anyways i have searched a bit on some forums and some say that this xbox psu does not output a 12 volts when its disconnected from the xbox console .
And also the 12 v rail is activated when the 5 vsb is shorted with ps-on .

Any ideas on this ? is it safe to keep 5 vsb shorted with ps-on and see if the 12 v is given ?

[SM-Piyes90]

Re: X-360 PSU ( PWM IC not having vcc voltage )

Ironically i have found that the enable pin was broke .

PSU is on now .

[Agent24]

Re: X-360 PSU ( PWM IC not having vcc voltage )

Good to hear!

[momaka]

Re: X-360 PSU ( PWM IC not having vcc voltage )

Any ideas on this ? is it safe to keep 5 vsb shorted with ps-on and see if the 12 v is given ?

Yes.
Short PS-ON to 5VSB and the power supply should turn on. No need for a resistor (though I always do it with one just in case ).

I have one Xbox brick that has a steady red light or no light at all when plugged in the wall. IIRC, these PSUs had either Samxon or Taicon caps in them (or possibly Ltec), so I wouldn't be surprised if there is a bad start-up cap in the 5VSB circuit.

[stj]

Re: X-360 PSU ( PWM IC not having vcc voltage )

probably full of dust and a stalled fan.

[momaka]

Re: X-360 PSU ( PWM IC not having vcc voltage )

probably full of dust and a stalled fan.

Actually no. I got two of them as a set. The one that was packed full of dust was working. This one is clean and not always working. Go figure.

[stj]

Re: X-360 PSU ( PWM IC not having vcc voltage )

maybe it's not full of dust because it has a bad fan - does the fan have a tacho output that could be used to shut the supply down?