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Reballed SMC - same behaviour anything else to check?

So a little bit of history on this one - originally came in with a spill - was mainly focussed around the clock chip and bios chip. I've removed both clock chip and bios chip cleaned it all up and then given it a new clock chip and fixed any oxidised pads underneath each. I've then ultrasonic'd...

Checked it - couldnt see any reaction of any PM_SLP signal when SMC_ONOFF_L was triggered. Luckily I've found another 820-000165A board in my pile of boards i've previously replaced and have got that one working with a new clock chip. Customer now happy so thats the main thing. Is the CPU / PCH...

Thanks yeah I must've caught the pulse at 1.08v when I measured it earlier it's a steady 3.2v Other voltages: PPVRTC_G3H - 3.3V RTC_RESET_L - 3.3v PCH_SRTCRST_L - 3.3v PCH_INTVRMEN_L - 3.3v PCH_DSWVRMEN_L - 3.3v PP3V3_S5 - 3.3v PM_DSW_PWRGD - 3.3v PP3V3_SUS - 3.3v PM_BAT_LOW_L - 3.3V PM_RSMRST_L...

Yes 3v3_SUS is 3.3v and PM_SLP_SUS_L is 1.08V. When triggering SMC_ONOFF_L I get slightly strange behaviour on PM_PWRBTN_L - PM_PWRBTN_L starts at a low voltagev 1v or so when I first apply power once I trigger SMC_ONOFF_L the voltage drops to 0v and then back up to 3.43v afterwards - it drops...

i usually check cpu power at the caps above the cpu but can confirm at L7310 the voltage is 1.8v. I've tried a clean bios posted on the forum for this board but still nothing no display. Are we looking at a dead CPU? I should add I checked for voltage on the 25mhz and 32khz pins out of u1900 and...

Thanks for you replies: Yes VCORE is present 1.05V, checked 3V3 SUS which is also present - have checked and have 3.3v at BIOS chip. Does anyone have a known good bios for this board? I've never had to flash this one before!

Got a strange 820-00165 in today - clean board no spillage - was quite a thick layer of dust on the top of it which i've cleaned off but have been unable to find any signs of corrosion anywhere. Board powers up but gives no display at all - caps lock doesn't react, usb mouse doesn't light up...

Hi Thanks for your suggestion! BKL_EN was 0V traced the problem down to the Pad under R7731 was corroded - not at all visible from the top! have since repaired the pad and put a new 200k resistor there and now backlight restored!

thought i'd just hop in here daniel - if your looking for somewhere to purchase a Crest from in the UK then take a look at sonikem - I got mine from them at a very reasonable price compared to everywhere else I checked!

Having an absolute nightmare trying to restore backlight to an 820-00165 which was liquid damaged. I had a small around of corrosion around the LCD connector which has cleaned up fine - most of the corrosion was around the backlight driver U7701 and its accompanying resistors. Having pulled the...

thanks all - i thought as much so have consigned this board to the scrap pile!

So i've got an 820-00045 board in for repair and the history given to me by the customer was the screen froze and the sound went odd then the macbook wouldnt give any display any more. On my testing: I've checked PP3v3R3v0_AON which is not shorted and is sitting at 3.31v as it should be PPDCIN...

my meter does read a little low normally - yes the battery is charging as normal. Keep meaning to invest in a better meter!

Thanks for your replies - can confirm after having replaced Q7180, U7100 and Q7130 again and also running a jumper wire for CHGR_PHASE from L7130 to C7125 the macbook is now charging and producing 12.3v PPBUS from the charger as normal. thanks for your advice.

Hope someone can help with this one as it's proving to be a complete pain. History: Macbook brought in with liquid damage and no power. Inspection revealed liquid damage around Q7130 which had also burned Q7130 and the CHGR_PHASE pad underneath. Smaller amount of liquid damage around U7100...

Yes that was with everything disconnected from the board. Decided to take a risk and pull the SMC off the board - looked fairly clean underneath if i'm being honest but testing PP3V42_G3H for shorts afterwards was showing 2.2k ohms and not the 45ohms it was before. It's pointing me to think that...

Given U7200 another look - can't see any other signs of corrosion around it. One interesting observation I have made is that the PP3V42_G3H rail appears to have quite a low resistance to ground 45ohms or so. I'm not sure if that is normal on this 2015 board as I do not have another one to...

Checked U1950 - looked clean but replaced anyway - unfortunately it hasnt made any difference. SMC has been reflowed also with no effect.

Checked for corrosion around U1900 - none visible. Replaced U1900 anyway from a donor board but same - still got cpu vcore but no chime/display. As for activity on USB - nothing at all with USB mouse or keyboard - if I plug a USB flash drive with a light on it though it does light up for a few...