Ok here's the situation: When I unplug the AIR pump fuse the fans run full blast like they should. If I turn on the A/C they come on low. I just changed the water pump temp sensor today. The new sensor is showing good ohm readings and the plug shows right at 5 VDC. Unfortunately, my fans will not operate during normal conditions. I've let the engine idle up to about the 3rd line on my temp guage before I pussed out and turned on the A/C. Does anyone have other ideas to check out?? I suspected the engine block temp sensor to be faulty at first but the water pump sensor is showing ohm readings consistent with the temp gauge. Thanks for any help you guys can give me.

 

The only way to tell what the pcm is actually seeing is to use a scan tool to monitor the temp and also the fan ON command. The pcm, itself, could be a suspect.

 

ouch that sounds painful (cost of pcm fix)

 

That is why the scan tool is needed to rule things out.

The cost of a pcm would not be too bad (used).