All three are always connected on these units:Traceour's pic only shows three pins , I would unscrew the top and investigate if all three are wired and or what the third may connect to or do if connected.
![IMG_2635b.jpg](/forum/data/attachments/56/56799-fe00d552d755833e28c5d51974c433bf.jpg)
The centre wire goes through the loom into a motor unit connector on the circuit board and this is encapsulated and sealed into the crankcase half, so no access for tracing.
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