I re-uploaded the image with the correct readings from my multimeter.
DVDdoug:
It seems strange to have 118V in a 230V device.
The device is rated for both 120V and 230V.
DVDdoug:
It looks like the indicator light is in series with the switch. But, that would mean the light is completely off when the switch is off.
It's not completely off. It's just dimmed. The ground wire from the switch is connected to the indicator light's ground, but the positive wire (blue) going to the indicator light is not connected to the switch.
DVDdoug:
Is there something else in the box we can't see? I see some bare wire or solder in the middle of the blue wire. What's that connected to?
I desoldered the blue wire so I could measure the current going through the indicator light.
DVDdoug:
Is there a bare wire connected to the bottom of the switch above where you labeled "rocker switch", or am I seeing metal inside of the box? Is that where brown is connected to ground?
The bottom wire (brown) on the rocker switch is actually positive. Not sure why they chose brown.
DVDdoug:
With the meter in the DC mode, most meters will measure zero (or near zero) when connected to AC. Depending on the meter, it may also measure zero in the AC mode when connected to DC. If you are truly measuring DC, you should see a minus sign when the connections are reversed. Try measuring a battery (DC) to see how your meter responds in the AC mode, or when you reverse the connections.
An AA battery in DC mode shows 1.54V and in AC mode 2.7V. When I try DC mode on the GND and VCC of the rocker switch, I get 67V when connected properly, and -67V when reversed. However the rocker switch is rated for 250VAC with no rating for DC. AC mode shows 129V (yes, 129V. It was 118V before I took the switch out). Reversing leads in AC mode shows 1.8V.