computercaverva
Member
Will do! Im out of the shop now but will check those in the morning! If those resistance readings are off replace the resistors of course and also the ISL6259 or is there a way to see if the chip is good on the board?
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Liquid Damaged 820-3115 Cyclical Fan Spin, PPBUS_G3H Voltage Jumping
- Thread starter computercaverva
- Start date
That is negligible, ignore it. What about pins 27/28?
Well PPBUS_G3H generation is simple... Pulsing is usually current sense but can be the ISL telling the FETs to do funny things and sometimes it's a combo of all three.. If current sesne is OK replace your 6259 and the FET's controlled by it Q7030 and Q7035 I believe.
computercaverva
Member
I replaced all of the current sensing resistors as they looked nasty and probably burnt, also replace the 6259 and the board powered on green light, fan stayed running however no post beeps with ram removed. The board then cut off and now has no signs of life, no more green light 0V on G3H and PP3V42. Is it possible that replacing U700 without replacing the FET's blew the 6259 and the ISL and FET's should be replaced together?
Always replace the FETs and ISL at the same time. And yes.. The fets screwed up the ISL and that's why it's not working. New ISL and new fets and try again.
See larossmann bad ISLs CAN cause 1/4 fan spin on 820-3115s