Fuse box voltage is 6V in Key position is off

[Neetman]

Hi there,
It looks like all the LEDs and parts, including the door lamps, are not powered. Sometimes it glows weakly, but I don't know what caused it. How should I troubleshoot?
I have confirmed that 14V is coming from the battery to the alternator. When ③ and ② come into contact as shown in the image, it drops to 6V.


67135
67136

[Rich]

Looks weird. Before we get too far can you pls verify the voltage?

You report 6V
The multimeter in photo 1 looks like 0.6V