SN0903049 u5110

This chip turns the SMC on. It is often placed on the corner of the board making it susceptible to liquid damage & death.

The SMC can't turn on without SMC_RESET_L being present. The _L means low - meaning the signal is "active" when it is low, or 0v. The SMC will be "reset" while this is low. The concept is that the SMC should not be turned on until the power rails have stabilized. This IC ensures that the PP3V42_G3H 3.42v power rail has stabilized prior to allowing SMC_RESET_L to go high. 

Check the pullup resistor for SMC_RESET_L that pulls SMC_RESET_L up to 3.42v before replacing this IC. If removing this IC does not bring SMC_RESET_L up, then replacing this chip will NOT fix your problem!

The job of this chip is not to "create" SMC_RESET_L, but rather, to keep it LOW(0v), in reset mode, until the power rail has stabilized. If you remove this IC and SMC_RESET_L is still low, you either have an issue with the SMC pulling the voltage down, or the pullup resistor/power supply creating the signal. 

Please also do check that the keyboard is not resetting the SMC, and that this is the proper chip for your logic board.