The saga continues on my heating & AC problem with my '88 XJSC V-12. I'm posting in the GENERAL TECH ? forum because i believe the HVAC was used in more than just the XJS & XJSC and might shed some light on my issue. To recap, my old system had been butchered by a previous owner. I purchased a complete center unit from ebay only to find out that the motors had been butchered as well. Found two good motors and installed the system. By the way ... Fun factor is -100 on this project! I consulted many wiring diagrams and got a great Delanair III Manual from a member of this site which helped greatly.

I have run all new vacuum lines to their respective routes. All plugs are perfectly matched except for the one in my center console that feeds the unit. From the wiring harness in the car I have a black plug with three wires. The delanair units' power plug has 6. How does that work? I made a video on youtube of the results of this project.


I am wondering about 2 things .... The first being the plug to the unit from the car. The old unit I took out was a MK-III, now whether it was factory or not I have no idea. The Delanair unit has a Gray plug and the car has a Black plug. ??? When I unplug the connection my right motor comes on low. If I touch the connectors it goes on what sounds to be medium. If I apply a little more pressure the fans go on high and when I plug the connection tight a solenoid clicks and then nothing.

The 2nd thing I'm wondering is if the Baby Grand is bad. You can see my delema in the video. Perhaps the solenoids aren't being told what to do by the control unit? I have no fan control, no temp control and no vacuum actuator response.

Sadly I only want my car to have a heater. That's what started this in the first place. If I didn't already have so much in it at this point I'd just rat-rod a basic system in it but I'm not that way. Thoughts or suggestions would be greatly appreciated.