Our Community is 940,000 Strong. Join Us.


92 Rad and A/c fans always on


sparky2eh
05-17-2007, 01:02 PM
Hi, I usually just lurk around here but I just bought my wife a "new" 88, 3rd in a row previously had an 87 and an 88. Anyway I got this "new" 92 which has the complete digital/push button heater and a/c control system and of course there is a problem with it :-)
The air flow out the vents, heater, defrost or whatever selection is very low no matter what the fan is set on. I removed the heater fan and it blows air like a sumbitch. Did not see any obstruction in the heater box. The temp control works fine hot to cold. The selector changes positions heater, defrost vent just very low air flow. I also noticed that the rad fan and a/c fan run all the time when the engine is running, even when I turn the heater and a/c off.
I was wondering if the problem could be the control unit or the fan temp switch or both? I checked vacuum to the controller and it is good. I checked the multi colored vacuum lines and they appear fine. I checked quite a few connectors and traced alot of the wiring and found nothing noticeable. By the way where is the rad fan temp switch? Or is it controlled by the PCM/ECM ?
I think both fans are turned on when the a/c is turned on which kind of makes me think it is a controller problem...... any thoughts? Thanks.

maxwedge
05-18-2007, 08:26 AM
The pcm controls a relay for the cooling fan, based on ac operation or temp. This may or may not be related to the blower fan issue. The blower power modules were problematic on these cars, it is around the top of the evap case under the hood. A wiring diagram may help you here, a basic one is available at autozone.com/repairinfo. A " real" shop manual is the way to go.

Add your comment to this topic!