Geoff Z
Some PCB's have a J3 6 pin connector. Others do not. Same part number with or without. The picture on GenService does not have a J3. I have never been aware of this. Can anyone explain. I am wondering if this PCB is used in generator models that have a stepper motor? I have pictures but they won't load.
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Geoff Z
Got them to load
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Peddler
Never noticed, and I don't ever remember using a J3 plug on these boards.
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Birken Vogt
We just got a governor controller for the Mitsubishi liquid cooled units and it has a similar connector and the old ones didn't.  I suspect it might be for initial programming or something.  That board has obviously been updated to surface mount, all the ones I have seen have been dog bone components. 
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Geoff Z
I do know it doesn't change functionality in anyway with or without the J3 connector. It was just a little unsettling to see that and not know what it is.
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UPS
That kind of connector is often used with a 2 pin jumper to set options, rather for an external connection.
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Geoff Z
There is that type connector and 2 pin jumper on the SMM
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JayH
It may be a JTAG connector used for low-level troubleshooting. It's not uncommon to find such on devices with embedded microcontrollers, and they're usually not well documented.
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