Well, I let the smoke out!

[Buick8]

'86 420 SEL US-spec: on my first big shakedown cruise this afternoon, smoke started pouring from under the drivers' side instrument panel; it smelled electrical. I turned the air conditioning off and it stopped immediately; finished the 150 mile round-trip without further incident (with AC off). System has been acting erratically: sometimes tries to heat and cool at the same time; blower is always in "auto" even when set to "low"; any help troubleshooting this complex system will be appreciated. Regards from Randy

 

[Buick8]

Smoke: part 2

Took a chance this afternoon; tried the air conditioning; worked perfectly. Looked underneath the drivers' side instrument panel, did not see any burned wires; however, noticed the outside temperature indicator, already had part of the display gone, is now completely dead. Could the temp indicator's sudden death result in smoke? :?:

 

[Benzene]

I guess it could if it burnt out, relays tend to smoke when they go aswell.
Looks like you found the answer.