Any ideas on how to troubleshoot AIR selector stuck in defrost mode on '96 Mustang 3.8L? Tried cycling several times no help. Next will probably disconnect Battery and start over.
By defrost, do you mean the air only blows thru the defrost vents? If so, then look for a vacuum line break or disconnect under the hood near the firewall. I had the same issue that was corrected by fixing a break in one of the lines going to a vacumm tree.
Looked under the hood..no disconnected lines. The air is only coming through the defrost vents no matter what the switch position(except off..then it is off). Could it be electrical?