Hello , My console works just fine , the fan stopped working i replaced 3 fans now none works .
I measured the pins for the fan (as shown below) .
it seems weird that the pwm voltage is 3.3v while it suppose to be 5V .
i tried supplying 5V directly to the fan . Also nothing .
Can someone guide me to a solution or an idea of where the problem could be coming from .
PS : I changed the connector also nothing changed .
PIN 1 : GND
PIN 2 Main Power : 12V / 0.2916 in DIODE MODE
PIN 3 (TACHO) : 2.09V / 0.9725 in Diode Mode
Pin 4 (PWM) : 3.3V / 0.5148 in Diode Mode
A PWM signal is needed for controlling the fan speed. A flat 5V injection does nothing in lack of informations.
Do you have the Ohms readings at the TACHO and PWM and a osci to check the signal form of the PWM?
PWM is a tiny bit higher than I would expect: my readings are
PWM: 6.5 MOhms
Tacho: 13 kOhms
At the PWM line is only one 33 Ohm resistor (R116 @ V1 SB board) (yellow marking at image) before the southbridge IC. If this resistor is in specs I guess there is a problem with the SB itself.
HAD one fan issue XSX came in today with 12v line shorted, sort it out but fan full speed spinning now.
This is the newer model with slight difference redesign layout. Checked diode reading PIN3/TACHO: 1.56v (48k ohm)
pin4/PWM: 0.77v (6,xMega ohm
NOT 100% sure if the R175 and R116 resistors value different from V1 DAY1 model makes any different but I replaced them according old schematic but still no luck… Guess maybe SB bad.
