I have a 1972 Electra 225 Custom Limited with the automatic a/c system. The vehicle has been restored by one of the POs and everything still looks, well, not like but close to new, incl. the a/c system and wiring. Too bad I have no heat nor cold air. While the latter could simply be caused by missing freon (not converted to R134a yet), I look to at least get the heat to work. I do have the FSM (Thanks, Teambuick!) and read thru it, yet the system appears to be "complex" at best, equipped with lots of sensors, relays, vacuum components and the programmer. I also used the trouble shooting list to eliminate some possible causes of malfunctions but did not succeed yet. Here are the symptoms on the car: The lever in the head unit activates the various settings (vent, lo/high, b/l, defrost, etc.), the fan is fast on hi and defrost, low on lo (although veeery low, hardly recognizable but I hear the fan) and blows through the different outlets in the related settings, Hi and Auto only come on after the engine has warmed up (as designed). However, the temperature dial in the head unit does not change the temperature of the air coming from the outlets. Here is what I found out on my car (in no particular order): visual inspection shows nothing unusual all fuses are good all vacuum hoses are connected (in the head unit, on the programmer, on the four or five way manifold on the firewall [what´s not needed is capped off] engine vacuum is there (defrost/vent door function, vacuum operated cruise control in functional) hot water comes from the engine, goes thru the heater core and comes back hot, footwell is dry all connectors appear to be connected, so is the sensor in the dash on top of the glove box a/c compressor clutch functional, compressor comes on when parameters are met lo relay on the firewall gets power and "hi" blower works as described above When laying under the dash pass. side and looking up to the air door arm and the head unit is operated though all of it´s settings and the temp dial is turned I cannot see the air door arm move! When reaching up and moving the arm manually, it takes a pretty lot of force, I´d say more than what the programmer can provide. Not sure if I am pushing against an activated vacuum actuator, but I did try in "DEF" and the air door should be open in this mode. I know that the air mix door is operated through a rod, activated by the programmer. The programmer gets it´s parameters from various sensors and the settings in the head unit. Again, the programmer seems to be a pretty complex device and of course I do not have the factory tester J-23678 to check it. Yet, this one seems to be the culprit as of now. A couple of questions: Is there a way to overrule the temperature thumbwheel in the head unit and force the programmer into "full heat" to see if it opens the air door? Can I check any diaphragm by connecting a vacuum pump and applying vaccum or possibly "force" the air door open by direct vacuum? Who sells or repairs programmers? RA, fleabay and the usual suspects don´t seem to have them.
My mechanic claims the a/c has to work - i.e. have freon in it - for the heat to come on, it would "all be one system". I am doubtful about this, would anybody know for sure?
Alex, NOT true! Unless something changed from 72, to 76, I had no freon in last winter in my 76 with Climate control, and had heat. I was going to suggest heater core issue, but it looks like yours is working. Kinda/sorta related, my Dad has a 1979 Town Coupe , and the heat has been an issue for a few years, typically comes on, then gets weaker, til there is almost no heat. And it's a "normal" system, not even Ford's C.C. I should add, I did run most of the time just the vent and turned up temp. It was plenty hot for me
Pretty good video, thank you! Yes, the design is pretty much the same than what I have in my 72 Electra. What you did is what I thought should work on my car, too: turn up the temp and the fan, get heat and not bother too much if it´s "automatic" or not. It´s just that the air door doesn´t move on my car, while the rest of the system seems to do what it should do. Now I need to find a way to check if the sensors work (resistance?) and if the temp dial is calibrated correctly. If they are ok, I am out of ideas.
Alex, was taking to a friend on FB about some issues I am having, and he mentioned a few things (one is an issue with V.I.R.'s used on 73 to 76, so it wouldn't be an issue with your car) the other was Cadillac Tim. Even though he focuses on Caddys, he said he can be a good resource . May want to check out his site, and perhaps contact him! http://www.cadillactim.com/
