Good morning, I'm new to this site and to Cadillacs. I bought a Eldorado for my son. The Air flow changes from coming out the dash vents to the floor. When it comes out the dash it seems to work fine. but the flow is noty good when it changes to your feet. How do I get it to stay blowing at the dash vents. ( '85 with 90K)

 

Hey Rollon: Your air should be in the dash vents only. If the mode door is not functioning properly it could cause this condition, the mode vacuummotor could also be to blame. Before going into your dash find the TAN colored wire coming out of the ECC programmer and follow it to the vacuum motor. Check all the connections and vac lines to the unit. If all seems fine maybe the vac motor is faulty and maybe the mode door is sticking or has an obstruction.

 

Sorry do you have a pix of the ECC? I'm not sure what I'm looking for.

 

Under right hand side of instument panel. One side of it will have yellow, white,orange, tan, and blue wire coming out. You want to follow the TAN wire.

 

OK I got behind the dash. In back of the glove box there is a box with vac lines and a box with wires going into it. I pulled the elect box and tapped on it. The a/c started working fine for a few minutes. I put the box back in place it stoped working. But if I tap on it it will come on and then go off. What is this box? some sort of relay?

 

Sounds like you have the ECC programmer located. There is a smaller box that has wires coming from it too and that is the ECC power module. The ECC Programmer has a Blk/Wht wire coming from it that is the diagnostic connector, through this you can determine how your unit is functioning. Programmer will set you back about $300 if it needs replacing.