820-2879 Green light No boot

PPbus_g3h 12.59v
PP3V3_S5present

u7840
1. PP3V42_G3H_PWRCTL 3.39v
2. 5V3V3_REG_EN 3.38v SMC_PM_G2_EN 3.38v
3. P0V9S5_EN 3.37v

4. P3V3S5_EN_L 0v diode .441 3.92m ohms

5. ground
6. PP3V3_S5 3.31v

7. S5PGOOD_DLY 0v .417 .544m ohms

8. RSMRST_PWRGD 3.35v

I've replaced u7840 due to corrosion and a 7ohm short on pin 4 P3V3S5_EN_L no change. checked u7840 on pin 4 before new installation and short went to OL. New values posted above. Am i missing a prerequisite?

What's wrong with P3V3S5_EN_L?
You already get 3V3_S5; didn't note the end "_L" in the signal name???

Trigger SMC_ONOFF_L and check for pulse at PM_SLP_S4_L, at same time.

No pulse on pm_slp_s4_L. Also Have 3.3v on SMC_ONOFF_L before trigger.

I hope you did the test correctly; read here:
Do not keep SMC_ONOFF_L tied to ground...

Known good keyboard to test.

You don't need the keyboard; read that thread...