[SOLVED]820-3208 no green light no power

[nate8organic]

got in a 820-3208 no power no green light, will not run on battery, voltage with charger plugged in only,
r7020 -20v
r6905 pin 1 -20v pin 2- 2.96v
d6905 pin 1- 0v pin 2- 2.95v pin3 - 2.67v
u5010 pp3v42_g3h - 1.76v
f7040 - ov on ppbus_g3h

i have tried replacing the isl, any idea what might be drawing the power down on pp3v42_g3h and why ppbus is not there?

Thanks
Nate

 

[dukefawks]

So an 18V voltage drop over R6905, that seems a lot and it must almost be smoking. So either a short on PP3V42 or after R6905.

 

[aprendiz]

bad R6905, check sense resistors on ISl, R7005, voltage on pin 2 from ISL.........

 

[nate8organic]

no smoke yet hah, i checked diode mode pp3v42 yesterday i was getting. .4v but after i had replaced the q7055 it seemed i was getting .1v in diode mode on f7040 so there must be a short on pp3v42 is my guess. can i inject voltage on pin 2 of the r6905 and how much can it take?

 

[dukefawks]

What does F7040 have to do with 3V42? Why do you guess there is a short on 3V42, can you not measure?

 

[nate8organic]

^^ hah sorry didn't realize what i wrote, or what i had tested yesterday got a flu right now head is all wacky. checked 3v42 =.321v in diode mode and its good. ppbus is .16v to ground. was also good. replaced the r6905 and everythings working.
thanks for all the help!