79 head cluster

[WallaceRoger]

I've been doing some more nighttime riding this year and really need to fix an issue with the cluster that's always been there.

Basically, none of the backlighting for the speedo and tach works. I've replaced the bulbs and when I had the speedo rebuilt a while back I made sure all the old connectors were put back together, but still no dice. The other thing I've noticed is when I flip the high beams on, the right side of of the oil light comes on.

Apart from that, everything works fine. Neutral indicator lights up when it's in neutral, the headlight, taillight, brake light and turn signals, including the cluster indicators, and buzzer work fine. So do the backlights for the temp, fuel and voltmeter. I opened up the fuse box in the false fuel tank and oddly the 10A fuse and related socket were totally removed at some point.

I know I probably just need to tear into it with a meter but wanted to see if anyone had any ideas that might save me some time.

[Fred Camper]

The high beam stays on and with a hot incandescent bulb it melts the divider and puts a window into the oil light chamber.

[Sidecar Bob]

When the instrument lights on my GL500 stopped working it turned out to be one wire between the connector and the first bulb that was full of green. That was the winter machine so the green wasn't too surprising but I'd bet yours is something just as simple.
One thing for sure: It isn't the fuse if the tail light is working.