Instrument cluster harness pins - electrical question

[Gibson]

I may know what causes this - but wanted to check with you guys and make sure.

So you know how a lot of the components in the instrument cluster share a common ground? (like all the illumination bulbs all share a ground) Well, I was mapping out the circuit on the back of the cluster cause I'm about to do some modifications - and I noticed something weird. I was using my multimeter on the Highbeam bulb trying to figure out which of the leads was the ground. So I tested for continuity with the chassis thinking "Whichever one has continuity with he chassis will be the ground"

But BOTH pin leads in the harness clip have continuity with the chassis! Is this because it is finding continuity back through its positive pin, then through a splice somewhere, then through a bulb somewhere to that bulb's negative side, and then to the ground/chassis?

I started testing the other pins in the harness and noticed a vast majority short out to the chassis (apparently).

If so, is there a simple way to figure out which of these lead are actually grounds, and which ones are just working their way back through the wiring somewhere?



Thanks!