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Shorted chips Q7630 and U7600 removed both and the shorts where gone from everywhere and resistance values normalised.
Replaced the chips (including Q7520) and short still gone. (blessed), made sure everything was still good and then plugged it in.
PPBUS was showing 12.6 Volts for awhile then...
Okay my multimeter must've glitched on me, disregard that bit - "showing the same resistances as PPBUS_G3H (which is showing 35Ohms)"
The resistance values between PPBUS_G3H and L7520 is 60 Ohms
Taking a reading with PPBUS_G3H to ground is also showing 60 Ohms
When taking a resistance value...
without U7501 attached PPBUS_G3H is still showing 60 Ohms
Every other coil is showing the same or similar resistances when put against PPBUS_G3H
With Q7520 also removed it doesn't show any significant changes and no coils showing the same resistances as PPBUS_G3H (which is showing 35Ohms)
Checked if U7501 is shorting the rail, but that seems like its shorting it even with that chip removed.
Removing F7140 I can see that Pin 2 is showing the 60Ohms (low resistance value)
trying to check every component on the lines but removing the capacitors still showing the P5VS4 rail as short.
Any component in particular do you reckon i should check out?
okay somehow I find that L7520 is actually showing short with PPBUS_G3H aswell.
ANd no some coils are showing 80 Ohms and some are showing way above that L7520 is showing around 2-5 Ohms.
I'll double check the situation with the fuse tomorrow.
Appreciate any help, thanks.
Quadruple checked Pin 23 and its only giving 0.6V and changes everytime i make an adjustment to the jumper (goes up to 1.5V)
Removing either capacitors does nothing to the voltages
Everything but fan and dc board connected.
Both capacitors giving the same voltages (1.7V) and looks fine.
Won't be able to check Pin 23 since I am doing this at home and microscope is at the workshop. But it seems good as there is continuity.
SMC_PM_G2_EN is present with 3.4V
PPBUS_G3H is 60Ohms
PP5V_S5 constantly going up towards infinity.
PP3V3_S5 around 0.483 KOhms
Short can only be seen when put between PPBUS_G3H and L7130
Hey another A1502 board for repair.
The board came in with not booting up and saw corrosion around U7501 with Pin 12 without a track which I made a jumper to pin 1 of R8140 and also replaced U7501. Unfortunately it hasn't made any changes and I also didn't take a complete list of the voltages I...
Hey everyone,
I have a slightly liquid damaged board which initially had no light but there was corrosion around U7501 so I replaced the the chip and also changed capacitors C7500 (one pad was completely destroyed so made a jumper going to Pin 23 of U7501) and C7503. No I have a green which now...
CHGR_DCIN: The voltage is 16.75V
27/28: gives 20Ohms
17/18: gives 0 Ohms ---- i'm gonna check my R7051 again, its giving 0 Ohms and not giving 2.2 Ohms and the R7052 is giving 0 Ohms aswell.
I am measuring resistance without power applied.
Thanks, Sam
Replaced R7005, R7051 and R7052 and its giving the same issues.
PPBUS_G3H still giving different value of 0.53V.
Forgot to mention but getting 3.24V on SMC_BC_ACOK and 3.4V on SMC_BC_ACOK_VCC.
Anymore suggestions or would you like any more readings.
Thank you.