Climate Control Programmer-odd issue

[CadillacFlashback]

When I first start my '78 Seville and place the head unit on Economy or any of the Auto settings, the system defaults to blowing cold AC air at high fan speed out of the dash vents regardless on the temp (fan will blow low speed on Lo setting).  If I jiggle the harness plug where the wiring connects to the programmer (passenger kick panel area) the system will immediately start working properly as to temperature, fan speed, and air distribution.  If I turn the car off and return in a short time it will continue to work properly, but if it sits for a longer time if always goes back to needing the "jiggle". I dont drive the car every day but it is the same drill every time I do.

Any suggestions on troubleshooting this?  The wiring and connections at the programmer all look great.

[benji808]

A "jiggle" fix is kind of textbook bad connection. I would pull the plug, inspect each prong individually, and spray a bunch of contact cleaner on both sides of the connection. To go further you could jump the connections and/or install a new plug. If that doesn't solve then either the jiggle is coincidental, or it's shaking something further up in the system, which you may be able to control for by how and where you jiggle it.

[bcroe]

If the original connector cannot be restored, you
might solder wires onto each side of a connection,
and run them thru a new connector that has noble
metal contacts, and enough current capacity. Leave
the original in place.  good luck, Bruce Roe

[Seville Life]

It can be a good idea regarding all electrical contacts to disconnect them and clean both sides with Scotchbrite, then coat them them a dielectric grease and re-connect.

They'll never play up again. I bought some excellent Permatex dielectric grease.

The Climate Control wiring for the sensors and temperature dial connections need to be right because they transmit an ohms voltage to the Programmer which provides the correct temperature air flow. I did mine and the system operates superbly. Paul