What am I missing? voltages on iPhone 5s lines

I am troubleshooting my first iPhone circuit. It is an iPhone 5s. I did diode readings on a bunch of circuits:

vcc main .359


PP1V8 .410

PP3V0_SDRAM .418

PP3V0_NAND .448


and so on….

I want to move on to testing voltages on the Chestnut outputs… I see in the schematic that VCC MAIN feeds into Chestnut and then there are several output lines. But I am stuck there.

When I attach the DCPS set at CC 4.2V, I read 4.2V on VCC MAIN caps. However, the outputs such as the 6v0 BOOST line coming out from Chestnut are all 0.000V. The BOOST line was measured at C329. PP5V7_SAGE_AVDDH is 0.000V at C52.

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