92 Cad Deville

[Captain D]

Hello All,

A couple of issues with my Cad. Has a whopping 180K, still runs strong, and quiet.

One: I never hear the (or see) the radiator fan running unless I have AC running. This leads me to believe that a relay is malfunctioning during normal ops. Engine seems HOT (especially) during prolonged periods of stop and go traffic. No idiot warning light indicating overheat. Is this normal Ops?

Two: All vacuum are new, and recently replaced. Heater does NOT work using ECC Auto function. Instead, the AC comes on blowing (of course) cold air. The only way I can get some sort of heat into cabin is to set temp upwards of 70 degreess and use econo control.

Anyone have ideas?

Captain D.

[maxwedge]

Fans go on at 225 aprox. The ecc works off various temp sensors and a programmer that moves the temp door, this would have to be checked through the diagnostic process in the control head, try caddyinfo.com for some info.

[Captain D]

Maxwedge,

Thanks for info. I'l start the diag process soon. At this point it is not earth shaking. However, being the perfectionist (bad habit and sickness) I would like to resolve.

Captain D

[636neil]

Couple of things to note, is this happening during a sunny day??? If so, you have to realize that there is a sun sensor on the dash in the passenger speaker grille on the dash. If this detects sun, the air will run until the cabin stabilizes, then the blower will slow down and adjust. This will happen even if it's cold outside.. Second thing, if this doesn't seem accurate, the air temp sensor in the cabin is not working correctly. What you will want to do to check this is remove the glove compartment, very easy to do and you know where the Cadillac is stamped in chrome on the dash??? Well that is a hidden return air vent and behind that is the sensor and there is a black hose that connects to the back side of that symbol. After you have removed the glove compartment, take a light and look inside and directly up where that symbol is and there should be a black hose, not real small in diameter, connected to the back side of that symbol. If it is not, your inside sensor will not work until you put it back on there. Very easy fix. Mine came off twice on my 93 and after the second time, I used a tie down to hold it from happening.

[Captain D]

Neil,

Thanks for the heads up. A wealth of information there. I will probably troubleshoot later today or tomorrow. Will advise on out come. Again... thanks

Captain D

[maxwedge]

Keep in mind the in car sensor is not the only sensor that inputs for temp control, there is an outside temp sensor also that has an effect on the temps, so sun on the dash may not have that effect, if it is 20 outside and 65 on on the dash., I believe there may also be one in the blower duct also.

[89DUBDEVILLE]

I had the same problem with cooling fan on my 89b deville. The switch that turns it on and off broke on mine and to buy a new one from cadillac it was like $300. So I bought a simple conector that I can turn on and off when ever.