AC Blower in front working intermittently
I am having the same or at least similar problem. First, I have a 98 Ford Explorer, 4WD, Engine Type E. I recently put freon in my system and the AC has been blowing cold for a few weeks. We had to take a road trip across country (From Washington State to South Carolina) and all was well until yesterday. The Front Blower stopped blowing. It would not work in any of the fan speed settings (and yes its a manual ac control). The rear blower works and blows cold air. Eventually during the long drive that day, the front blower started working again. Then after turning the vehicle off for gas, it once again stopped working. I did some research and figured it might be the Blower motor resistor.
I replaced that, and before mounting it I tested to see if it fixed my problem but it did not. So I mounted it back on anyways, thinking maybe, just maybe it needed to be mounted to work properly.(Keep in mind that when I took the old one off, it was horribly rusted, so I am guessing the connector is also rusted but I had no way to clean those connections.) Anyways, after hooking everything back up, I cranked the truck up and tested the ac blower and voila it worked.
Now don't get all excited, because my victory was short lived. I turned the vehicle on and off a couple times, the blower kept working and I felt victorious. Then it stopped working again. My next thought was maybe it is the blower motor itself or the fan speed switch. I took the blower motor off, and I tested it to see if it worked. How I tested it was, I took two wires and clipped one to my vehicles battery ground side and the other to the positive side. I then took those wires and held them against each terminal on the motor and the motor immediately started spinning. To me, that said the motor is good. I re-installed the motor and then I went out to Auto Zone and for $10 bought a new fan speed switch.
I replaced that switch, and before mounting everything back, i checked to see if my problem was fixed. Indeed it had fixed the issue and the blower motor was once again working, at least at first. I re-installed everything and then I turned the vehicle on then off a few times messing with the switch each time. All was well and I boasted to my wife what a genius I was. She reluctantly acknowledged and then told me I had some other honey-dos to tend to.
Later, to my surprise, when I hopped back in my truck and cranked her up, the blower motor yet again failed to work. I am at a loss here unless there is some kind of short or loose wire somewhere. Perhaps that Resistor Wiring Harness needs to be replaced? Any relevant help or advice is greatly appreciated!! Its extremely hot this summer and I still have a long ways to travel with 3 kids and I need to get this fixed ASAP! Thanks!
