Missing Wire for Coolant Reservoir Sensor

[CWB]

2000 E39 528i

Replaced the original Coolant Reservoir. (Later style, black tank)
Surprise, no sensor installed into bottom of Original Tank and...
*there is no wire to be seen anywhere to attach to new coolant reservoir sensor*.

Where should the sensor wire originate from?

Have researched and researched.
Cannot, so far, find any specific helpful information.
TIA

[BimmrMeUpSnotty]

Some EThoitynynes don’t have that wire.

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It won’t leak, even without the sensor.