Originally Posted by 93RedSled-SSE
See if I can make this sound technical enough to get away with it...
As a member of the 6
*, I have found that wearing your bi-focals upside down is a great aid when working under the dash.
Next time I see someone at Walmart with dirty hands and his glasses upside down, I'll know what he'* been up to.
As for gears cracking, I can't validate this at all, but I think age has more to do with it than merely the HVAC controller going into a cal mode. My gut feeling is that after time the plastic gear gets brittle and begins to crack. Disconnecting the battery exacerbates the problem when the HVAC controller runs the airmix door to its limits and is pretty much the nail in the coffin for an already compromised actuator. That'* the Gospel according to Stan, and is no-way based on fact...just suspicions.