00165 boots with SMC Bypass or with IO cable disconnected

[grmacs]

I've tried multiple other IO boards and cables. Board will stay running if IO cable is plugged in after it starts. CHecked VSENSE and ISENSE readings related to the SMC. ISL has been swapped. No change in Adapter Sense, SMC LID, FINSTACKSNS_ALERT_L, SMC_BC_ACOK or the SDA/SCL lines with cable connected or disconnected. I'm guessing theres a sensor reading being sent when the cable is connected that prevents the board from starting?

Guessing I need to change the SMC, I tried reflowing it. But I'm confused as to why the board will start with cable unplugged.

 

[piernov]

Of course you are using a genuine Apple Magsafe2 that's known to work with other 11"/13" 2015 boards right?

 

[2informaticos]

Try known good LIO board/flex.
Should discard first a problem from LIO side.

 

[grmacs]

Yes. As I mentioned tried multiple boards and flex already. Yes also using ms2 charger 85w

 

[2informaticos]

Do not insist to connect/disconnect LIO flex with charger, or battery plugged.
3V42_G3H is present there and you can damage J9500, or LIO flex/board connectors.

The MLB makes any start attempt if LIO flex is connected?
Check for pulse at big coils at least.

 

[piernov]

If it works properly when plugging in DC-in FFC after turning it on without it, it's very likely caused by SMC not liking the Magsafe and pulling PM_BATLOW_L low.