service light on with blank white screen

Hi Canada1427,

The service manual in the Documents section says 

1. Check A05 UI PCB for 3.3 V to ground at C96 and
2.5 V to ground at C93.
– If either one is not present, replace the A05 UI PCB.
2. Check P21 for 3.3 V to ground.
– If 3.3 V is present, check or replace the W18 UI Flex Cable.
– If 3.3 V is present, replace the A05 UI PCB.
– If 3.3 V is not present, replace the A01 System PCB."

Some of the newer models act funny in this way when the clock battery is dead. So maybe check that as well. 

Good Luck!