> When these boards go through our production testing, which includes
> several cycles of hot (85C) and cold (-40C) temperatures, we find
> that the solder bond between the PCB pad and the connector pin fails,
> which in turn causes the unit under test to fail.

My first question would be what sort of strain relief is there in the lead.=
 It sounds to me like it is not the solder joint at fault, more that when t=
he metal lead shrinks as it cools it pulls the lead off the pad. If there i=
s no loop in the lead to give it some expansion/contraction ability the fau=
lt you are seeing is exactly what I would expect.

For space qualified assembly work all leads like you mention should have so=
me form of Z strain relief in them. The sort of temperature range you are t=
esting to is the non-operating survival temp range we would use.


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