The radiator cooling fans are supposed to run when a/c is turned on but do not. The a/c clutch does engage. Cooling fans work ok on engine temp. Fuses ok. I suspect "Powertrain control module relay" How do I verify or is there something I am missing??
Cooling fans do not run with Airconditioning on 1996 Ford Windstar
by Visitor in Rosebud, MO on October 07, 2010
ANSWER by DaveJHM on October 07, 2010
This is a good one. You have two electric fans on the vehicle. Both have a high and low speed function - they work together. I suspect you have only high speed operational, and low speed does not work. My thought is that when the fans finally come on, the temperature is pretty hot. But when low speed fan is desired (as with A/C and not as hot temps), it does not turn on. Would take some checking around to make sure. Checking engine temperature when the high speed fan kicks on. Checking for voltage at the CCRM (Constant Control Relay Module) that controls the fan operation. Your PCM relay could be at fault, but I doubt it. More likely to have a faulty CCRM...have seen this before in Taurus/Sable/Windstar (all similar).