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Yeah then your charging circuit is suspect if that's the case. Tried known good battery? Post exact voltages as 2informaticos explained. Also check resistance between pins 17/18 and 27/28 of the ISL
SCL and SDA seem to be jumping around within the range 3.43 to 3.33 V. So I get 3.43 one second then 3.33 / 3.39 /3.34 /3.41 etc
These readings are without battery.
SCL 0.499 V Diode Mode
SDA 0.497 V Dode Mode
I'm sorry but I don't have another board.
Thnx M
Pulsing SCL/SDA could be sign of I2C signals from SMC.
In this case, the battery is first suspect.
Don't waste more time, untill get a known good battery to test.
Just post Q7155 voltages, charger w/ and w/o battery connected
Should there be pulses on SCL/SDA or should it be a constant voltage and if constant what voltage should I expect to see? 3.43?
Also were the diode measurements I gave you a good sign or bad sign?
If we put the battery aside for now why do you think I don't get fan spin with no battery and just charger unless I bypass the SMC?
Ooops, still not starting from charger only?
Are you 100% sure using original Apple charger 85W?
Of course no fan, as normal behaviour on this board.
Fan spins later, after CPU gets hot.
Yes proper charger
yes I know about the fan not spinning until cpu warms up
you didn?t answer my questions in my last post?? Well? I need you super skills of deduction
Proper test of I2C protocol for SCL/SDA lines can only be done with o-scope.
Should see something like in attachment.
Diode mode on SCL/SDA lines shouldn't show more than 1% difference for a good board; in fact is likely less than 0.5%.
"why do you think I don't get fan spin with no battery and just charger unless I bypass the SMC?"
You just told being aware of no fan spin at start.
On SMC bypass mode is normal that fan spins at max from start.