[s-cars] climate control

[Bill Mahoney]

Doug,
Other listers may know better, but in my experience, but sounds like it
could be one of these 'cold solder' joints that crack and cause
mysterious problems that come and go.  (btdt on my sony tv)
Now, what circuit board of yours might be causing this 'may' be
detectable by waiting for symptoms to appear again and then applying a
'high tech' jiggle of wires or circuit boards around suspect areas to
see where the problem may be corrected.
i.e. what wires were you moving or circuit board were you tapping on
when the problem disappeared.
I might suspect a loose or broken (intermittent) connection on the fuse
panel, a defective relay on the central electric panel or the auxiliary
relay panel (engine compartment drivers side top left.)
Heres a link describing some cold solder issues as they pertain to an
ecu:
http://www.bsecorp.com/tech/bdtecb102.pdf
HTH
Bill M  -Electrical Engineer, Not