Sal: JAX makes good points, but I�d like to think about this differently.
It sounds like the poorly soldered connection is lifting the whole connector, so that termination floats on top of the solder, rather than submit to the wetting force and be drawn down to the pad. As a result, the good terminations on the connector probably have a greater than expected spacing between the pad and the termination, producing weaker solder connections on all terminations on the connector, which is the reason you�re seeing an increased stand-off height of the locating pins after reflow.
Depending on visual inspection to catch soldering faults is a particularly dangerous situation, making you wonder: * What portion of these connectors are faulty and slip by the inspectors? * What portion of these solder terminations look good, but are really marginal?
Two things that you might consider: 1 Possibly: Flux is burnt-up before the solder connection can be made. 2 More Likely: Component (connector) has a level or a type of contamination that your flux can not remove.
How do you reflow these components during rework?
Good luck Dave F
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