Check PM_PWRBTN_L for pulse (at same time).
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820-00034-A 2 led on, fan on, no chime/screen
- Thread starter yair37
- Start date
Very strange; PM_PWRBTN_L is pulled-up to 3V3_S5, not to 5V.
What is the exact 3V3_S5 voltage, when you have 4.7V at PM_PWRBTN_L?
What is the exact 3V3_S5 voltage, when you have 4.7V at PM_PWRBTN_L?
But you've said first LED is steady on.
3V3_S5 shouldn't pulse in such case.
3V3_S5 shouldn't pulse in such case.
Still a problem on U7600 area; pay atention to 3V3_S5 area.
Check all traces and adjacent components.
REG_P3V3S5_PGOOD goes high?
Check all traces and adjacent components.
REG_P3V3S5_PGOOD goes high?
030 is very low reading for 3V3_S5.
Wait 10s after power is removed and check again.
Wait 10s after power is removed and check again.
Then you have a bad IC, or filter cap connected to 3V3_S5.
I doubt you can heat something with such resistance value.
But you can try; sometime the bad IC can enter in thermal avalanche.
But you can try; sometime the bad IC can enter in thermal avalanche.
C7660 voltage pulsing?
Also check R7693 pin 2.
Also check R7693 pin 2.
Very strange; L7650 shouldn't have voltage at all, if missing EN2 at U7600.
Check all 5V_S4 related components at U7600 area.
May need to change Q7650/55.
Check all 5V_S4 related components at U7600 area.
May need to change Q7650/55.