Cadillac Repair: heater problem/92 Deville, vacuum gauge, vacuum line

Question
Automatic setting for heat does not operate.Climate control center operates code diagnostics.Defrost setting works.Blower is operational.Heat is fine on defrost.Actuator does not operate blend- air door.Checked all vacuum lines from manifold in engine compartment,both lines are connected to vacuum tank.visual inspection so far,don't have vacuum gauge to check lines.Disconnected rod from actuator to blend-air door,door moves easily,and heat then operates normally,all vents operate.In your experience,is actuator a more common cause of problem?Please explain how vacuum works with programmer,in relation to actuator? Thanks,   Ray.

Answer
Check the BLACK plastiv vacuum line at the multi-colored vacuum block assembly at the programmer located under the dash on the drivers side for vacuum with the engine running. To remove the vacuum block assembly you will find a 7mm nut in the center of the vacuum block that must be removed using a deep 7mm socket and ratchet.

If you have vacuum at the black vacuum line then your problem is with the programmer motor.

Please e-mai: onlineautohelp@msn.com for numerous pictures and test procedures which are NOT allowed on this persons website.

You can get all the informatio to diagnose and fix this problem by e-mailing:

onlineautohelp@msn.com