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820-3437B not turning on
- Thread starter mushr00m
- Start date
"PPBUS_G3H = 8V"
ALWAYS post EXACT voltage for PPBUS_G3H (without battery)!!!
Check for pulse on all other coils; at same time with L7520.
ALWAYS post EXACT voltage for PPBUS_G3H (without battery)!!!
Check for pulse on all other coils; at same time with L7520.
Plug power cord appears for 1sec green light
Turn off
Then it turn orange
It had fan spin in a loop for a 30secs and stopped
PPBUS_G3H = 8.58v
PP3V42 = 3.41v
PP5V_S5 = 5v
PP5V_S4RS3 = tries to go to 5V and back to 0V in loop
PP3V3_S5 = 3.3v however after 5s with multimeter it goes to 0 and crazyly tries to go to 3.3 unstable and then gets stable
Replaced U7501... Still same behavior with the cooler and lights changing.
PP3V3_S4 = 0.3 then tries to go to 3.3 and back to 0.3 in loop
L7520 = TRIES TO GO TO 5V AND THEN BACKS TO 0 IN A LOOP
Turn off
Then it turn orange
It had fan spin in a loop for a 30secs and stopped
PPBUS_G3H = 8.58v
PP3V42 = 3.41v
PP5V_S5 = 5v
PP5V_S4RS3 = tries to go to 5V and back to 0V in loop
PP3V3_S5 = 3.3v however after 5s with multimeter it goes to 0 and crazyly tries to go to 3.3 unstable and then gets stable
Replaced U7501... Still same behavior with the cooler and lights changing.
PP3V3_S4 = 0.3 then tries to go to 3.3 and back to 0.3 in loop
L7520 = TRIES TO GO TO 5V AND THEN BACKS TO 0 IN A LOOP
"Check for pulse on all other coils; at same time with L7520."
RAM, PCH, CPU???
RAM, PCH, CPU???
Sorry I can only measure one coil at time... Not sure how to measure other coils at the same time with L7520
However measurement below
L7320 = Goes to 1.6V and back to 0V in loop
L7310 = Goes to 1.6V and back to 0V in loop
L7630 = Goes to 1V and back to 0V in loop
L7430 = Goes to 1.2V and back to 0V in loop
L7520 = Is doesnt show 5V on the multimeter but it shows that tries to go high and then back to 0V
L7560 = 3.3v stable
L7130 = 8.58 stable
L3095 = 0V
L7701 = 0V
However measurement below
L7320 = Goes to 1.6V and back to 0V in loop
L7310 = Goes to 1.6V and back to 0V in loop
L7630 = Goes to 1V and back to 0V in loop
L7430 = Goes to 1.2V and back to 0V in loop
L7520 = Is doesnt show 5V on the multimeter but it shows that tries to go high and then back to 0V
L7560 = 3.3v stable
L7130 = 8.58 stable
L3095 = 0V
L7701 = 0V
So you get pulse even on CPU core.
Check pins 7 & 3 of U1950.
What happens if try to start in SMC bypass mode?
Check pins 7 & 3 of U1950.
What happens if try to start in SMC bypass mode?
PLT_RESET_L pulsing too?
No pulse at all, for sure?
Check for pulse at CPU_VCCST_PWRGD and CPU_VR_READY.
Check for pulse at CPU_VCCST_PWRGD and CPU_VR_READY.
Check U1930 traces and solders.
Be sure R1931 is good.
Be sure R1931 is good.
Pin 4 should pulse to 1V.
If not, change U1930...
If not, change U1930...
Sure no pulse at pin 4?
With pulse on pins 1 & 2, pin 4 MUST pulse too.
Check traces and solders of U1930.
Check traces and solders of U1930.
Not visual, use buzer mode on multimeter.