820-3435 Not powering on, orange light on charger, no liquid

[fmcolon]

Hi. I am new to Macbook logic repair and am trying to get a Macbook Air to power on.

Charger goes from green to orange, no liquid damage. I thought older Macbooks had a green light if the battery wasn't plugged in. Anyway, here are some measurements I took,

PPBUS_G3H @ C3080 8,57v

PPBUS_S5_HS_COMPUTING_ISNS @ R7202 8.59v

PPBUS_S5_HS_OTHER_ISNS @ C7500 8.59v

PPDCIN_G3H_ISOL @ R7110 15.15v

PPDCIN_G3H @ R7110 3.98v

PP3V42_G3H @ C5006 3.42v

PPVRTC_G3H @ C1910 3.32v

PP5V_S5 @ C7505 5v

PP5V_S4RS3 @ C4690 Goes to .9v then to 0v

PP3V3_S5 @ C3550 3.3v

SMC_RESET_L @ Pin 5 U5110 3.39v
I am not sure where to go from here. I haven't tested a known DC board but have one coming in early next week. Any ideas?

 

[dukefawks]

PP5V_S4RS3 @ C4690 Goes to .9v then to 0v

So the board is probably power cycling. Was this liquid damage? History?

 

[fmcolon]

No liquid damage. Just decided to not power on.

 

[JohnB8812]

CPU VCore pulsing as well? If no, check all rails for shorts.

 

[fmcolon]

Vcore is pulsing as well at L7310

 

[dukefawks]

If this is 100% no liquid and 100% no drop and 100% not fucked with then the BIOS is the first thing to try at this point.