FE/FC 501 FE wiring mystery

Okay, I confess I hate reading wiring diagrams - I tried using the shop CD. My 2015 FE landed in my barn with only its second rear tire, original front and no evidence it had been ridden much. The PO reported the ODO freaked out. I pulled the mask and found that one of the 4 leads out of the speedo (purple/blue) was disconnected from the red/white pair off the speedo pick harness. I plugged them in the speedo senor stopped working - it would not power up when the front wheel rotated but the speedo would power up manually and the low fuel light came on. It did not record any mileage or hours. I haven't ridden it since I disconnected the pair again, but the speedo energizes as soon as I spin the front. There are two pairs off of the pick up harness with a yellow shink wrapped connection in the background of the picture. To be clear, off the speedo wheel sensor pick up harness, two pairs are at the mask/speedo; a red/black plugged into the blue/gray and the other a red/white. They can't be crossed as the plugs will not mate. The 3rd plug is an orange/white/green trio to a red/white orange and the 4, also a trio, of red/black/brown to brown/brown/orange, both of which are routed under the tank to the main harness.
I did two rides before I reconnected the purple/blue-red/white the trip od seemed to be accurate, but I didn;t notice if the cumulative odo was right, this reading was off according to the PO,

Milage aside, anyone have any idead what might be going on - defective speedo? Defective owner? All of the wiring looked new and I added some protection to exposed wires- I've done this on the last dozen bikes and never had a wiring failure - I didn't do a continuity check on the suspicious 2 wire connection but i will. I'm just hopefull there is aEE or wiring wizz in the forum that has a clue.

Thanks all

Did you change or check the internal battery in the speedo? There are some turn signal wires unused behind the mask as well.

I didn't put a multi meter on since the speed activates with a button push and stays on the preset duration before it auto shuts off. It is keeping time and it was functioning off wheel movement as long as the connection of the mysterious 2 wire plug.

Looked at the parts fiche and the oem speed sensor harness only has one 2 wire plug. I cut the yellow shrink wrap and found two soldier points for the additional plug. I have no idea what it was supposed to do but it sure isn't a factory event.

Anybody know what the purple/blue lead off the speedo/computer is supposed to plugged into or is it open????