Hi all,
I’ve just read through a ton threads on multiple forums and haven’t seen this exact issue: 2010 f150 Lariat SCrew, auto hvac controls. A month ago, my blower stopped blowing completely. Fuses and relay seem fine, so I replaced the blower motor but no change. I then replaced the blower motor resistor, and that seemed to fix it. The blower was blowing like normal, controls working properly, AC blowing cold. Then, after about a week, a new issue started. The blower blows hard for about 2 seconds, then shuts off for about 10 seconds. On for two, off for ten, very consistently, over and over. I have an hour daily commute and it does this the whole time. I thought it was a faulty new resistor, so I got a new one and replaced it again. Same exact issue, only this time it never worked properly for a week first.

Anyone experience this? Any suggestions?

thanks

 

I would check the switch.

 

What kind of system do you have? Is it controlled electronically?

 

Yes, it’s controlled electronically. Sync system with auto hvac control. Actually just discovered today that it seems to work fine when I use the touch screen climate controls to manually set it on a middle fan speed. Does the intermittent thing again as soon as I go back to auto or manually set it on the highest fan speed. I’m thinking this brand replacement blower resistor is just not a good compatibility. (BWD from advanced auto parts...)