'77 R100S: No GEN or Oil light

[ZombiePotatoSalad]

I'm resuming work on my bike now that it's warming up outside. However, I'm getting no light on my GEN or OIL indicators.

I've decided to take off the front engine cover, and I find a mouse nest. So I get to clean off all that gunk.

I have a neutral light, I'm getting spark to the plugs, pulling the oil sensor wire at the bottom of the crankcase shows a strong light on the test probe. However, when trying the blue wire that has a connector by the starter relay, the light is weak when touching the test light to the wire that runs down from the main harness.

[SteveD]

As it's two adjacent dash lights my first thought was the circuit board connections in the instruments. If oem and 47 years old then maybe the copper connections for the bulbs are buggered?

[gspd]

The GEN and OIL light bulbs should always have power to them with the ignition 'ON'

To activate the OIL light, the wire at the oil switch provides the ground . (The terminal on the switch is 'ground' when no pressure.)

To activate the GEN light, the blue wire at the voltage regulator provides the ground. (That terminal on the regulator is 'ground' when system is not charging.)